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Frontiers of Optoelectronics

Front. Optoelectron.    2018, Vol. 11 Issue (3) : 209-244     https://doi.org/10.1007/s12200-018-0819-8
REVIEW ARTICLE |
Generation and detection of pulsed terahertz waves in gas: from elongated plasmas to microplasmas
Fabrizio BUCCHERI1, Pingjie HUANG2, Xi-Cheng ZHANG1,3()
1. The Institute of Optics, University of Rochester, Rochester, NY 14627, USA
2. State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, China
3. The Beijing Advanced Innovation Center for Imaging Technology, Capital Normal University, Beijing 100037, China
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Abstract

The past two decades have seen an exponential growth of interest in one of the least explored region of the electromagnetic spectrum, the terahertz (THz) frequency band, ranging from to 0.1 to 10 THz. Once only the realm of astrophysicists studying the background radiation of the universe, THz waves have become little by little relevant in the most diverse fields, such as medical imaging, industrial inspection, remote sensing, fundamental science, and so on. Remarkably, THz wave radiation can be generated and detected by using ambient air as the source and the sensor. This is accomplished by creating plasma under the illumination of intense femtosecond laser fields. The integration of such a plasma source and sensor in THz time-domain techniques allows spectral measurements covering the whole THz gap (0.1 to 10 THz), further increasing the impact of this scientific tool in the study of the four states of matter.

In this review, the authors introduce a new paradigm for implementing THz plasma techniques. Specifically, we replaced the use of elongated plasmas, ranging from few mm to several cm, with sub-mm plasmas, which will be referred to as microplasmas, obtained by focusing ultrafast laser pulses with high numerical aperture optics (NA from 0.1 to 0.9).

The experimental study of the THz emission and detection from laser-induced plasmas of submillimeter size are presented. Regarding the microplasma source, one of the interesting phenomena is that the main direction of THz wave emission is almost orthogonal to the laser propagation direction, unlike that of elongated plasmas. Perhaps the most important achievement is the demonstration that laser pulse energies lower than 1 mJ are sufficient to generate measurable THz pulses from ambient air, thus reducing the required laser energy requirement of two orders of magnitude compared to the state of art. This significant decrease in the required laser energy will make plasma-based THz techniques more accessible to the scientific community, as well as opening new potential industrial applications.

Finally, experimental observations of THz radiation detection with microplasmas are also presented. As fully coherent detection was not achieved in this work, the results presented herein are to be considered a first step to understand the peculiarities involved in using the microplasma as a THz sensor.

Keywords terahertz waves      Terahertz Air Photonics      generation and detection      elongated plasmas      microplasmas     
Corresponding Authors: Xi-Cheng ZHANG   
Just Accepted Date: 22 June 2018   Online First Date: 07 August 2018    Issue Date: 31 August 2018
 Cite this article:   
Fabrizio BUCCHERI,Pingjie HUANG,Xi-Cheng ZHANG. Generation and detection of pulsed terahertz waves in gas: from elongated plasmas to microplasmas[J]. Front. Optoelectron., 2018, 11(3): 209-244.
 URL:  
http://journal.hep.com.cn/foe/EN/10.1007/s12200-018-0819-8
http://journal.hep.com.cn/foe/EN/Y2018/V11/I3/209
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Fabrizio BUCCHERI
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Fig.1  Electromagnetic spectrum. The terahertz frequency band bridges electronics and optics (modified from http://www.physik.uni-kl.de/en/beigang/forschungsprojekte/)
Fig.2  Typical measured THz waveform (a) and its spectrum (b) obtained as the magnitude of its Fourier transform. The oscillatory tail after the main pulse (Dt>1), corresponding to absorption features in the spectrum, is an effect of the propagation of the pulse through ambient air
Fig.3  Example of THz time domain spectroscopy (a). A reference trace (solid black) and a sample trace (solid red) are acquired without and with the sample inserted in the THz path respectively. Compared to the reference trace, the sample trace has: a reduced amplitude, indicating the presence of absorption; a time shift, indicating the addition in the THz path of a material with refractive index greater than one; several oscillations in its tail, indicating the presence of resonant absorption mechanisms. (b) Fourier transform of the reference and sample traces (modified from http://www.physik.uni-kl.de/en/beigang/forschungsprojekte/)
Fig.4  (a) ABCD setup sketch: the laser probe (w) and the THz beam are collinearly focused through two electrodes generating a signal at the second harmonic 2w. A high voltage square wave biases the electrodes allowing the coherent measurement of THz radiation. (b) Measured second harmonic intensity as a function of the third order nonlinear susceptibility of the gas employed. All values of nonlinear susceptibility are normalized with respect to nitrogen (Reprinted with permission from Ref. [17], copyright 2012, Elsevier)
Fig.5  (a) THz-REEF geometry. The THz pulse is focused on the plasma generated by the laser probe beam, collinearly with the laser propagation direction. The fluorescence emitted by the plasma can be collected by any angle. (b) Electrons accelerate in the THz field and collide with neighboring molecules. (c) Plasma fluorescence intensity spectrum with (red) and without (black) THz field. The fluorescence lines are all equally enhanced. (Reprinted with permission from Ref. [116], copyright 2011, IEEE)
Fig.6  (Top) Time resolved plasma fluorescence intensity for the cases of antiparallel (blue), symmetric (red) and parallel (black) electron drift velocities. (Bottom) The subtraction of the parallel trace from the antiparallel one reveals the THz waveform (Reprinted with permission from Ref. [17], copyright 2012, Elsevier)
Fig.7  Acoustic plasma emission measured with a high frequency microphone placed 10 mm away from the plasma with (red) and without (black) THz illumination. The inset shows the setup for THz Enhanced Acoustics measurements (Reprinted with permission from Ref. [17], copyright 2012, Elsevier)
advantages disadvantages
can be implemented with ambient air amplified laser systems, expensive and bulky, are required (laser threshold)
useful bandwidths (>60 THz) low optical-to THz conversion efficiency
high peak electric fields (>MV/cm) intense optical radiation requires higher safety standards and poses hazard
no damage threshold low detection sensitivity
remote operation critical alignment is required
higher spectral resolution
(no Fresnel reflections)
no absorption features
Tab.1  Advantages and disadvantages of THz Air photonics
microplasma elongated plasma
length:<1 mm
width:<1 mm
length: few mm up to meters
width: ~ 100 mm
tight focusing of the laser (NA>0.1) loose focusing of the laser (NA<<0.1)
higher peak laser intensity (>5 × 1014 W/cm2) lower peak laser intensity (~1 × 1014 W/cm2 [20])
higher peak electron densities (~ 1018−1019 cm3) lower peak electron densities (~ 1015−1016 cm3)
position does not change with laser energy position changes with laser energy
lower laser energy threshold (<1 mJ) higher laser energy threshold (~ 30−50 mJ)
Tab.2  Comparison between elongated plasma and microplasma
Fig.8  THz waves are emitted by the ambient air microplasma obtained by focusing the laser excitation through a high NA objective. A high resistivity silicon wafer (filter) is inserted in the THz path in order to block the pump beam. The waveforms are retrieved with electro-optic sampling. The THz generation portion of the setup can be rotated about the position of the microplasma in order to study the angle-dependent emission from the source. The inset is a picture of the microplasma created by focusing laser pulses with energy of 65 mJ through a 0.85 NA air-immersion objective as seen through a UV bandpass filter. The laser excitation propagates from right to left. The plasma is imaged from the side with a commercial iCCD camera. The fluorescence profile is Gaussian. The FWHM for the longitudinal and the transverse fluorescence intensity profile is (36.7±8.7) mm and (28.5±8.7) mm respectively. List of abbreviations: HWP, half wave plate; OBJ, objective; OAPM, off-axis parabolic mirror; POL, THz polarizer
Fig.9  (a) Density plot representing the coherent angle-dependent emission from a microplasma generated with laser pulse energy of 65 mJ. The plot is obtained through spline interpolation of ten THz waveforms recorded at different detection angles in 10° intervals starting from 0°. Each waveform is normalized to the highest value of THz field recorded in the set. Dt is the time delay between the pump and the probe beam. (b) THz pulse energy as a function of detection angle. The pulse energy is extracted from the THz waveforms displayed in (a)
Fig.10  Measured THz waveforms at detection angle of 80 degrees for a laser pulse energy of 65 mJ (top) and of 660 nJ (bottom). For clarity, the plots are offset and the waveform measured at 660 nJ is magnified 600 times
Fig.11  (a) Measured THz spectral amplitudes with 〈110〉 -cut ZnTe crystals of different thicknesses: 1 mm (red curve), 0.22 mm (black curve). The black dashed curve is the measured experimental noise. (b) Density plot representing the angle-dependent spectral emission from a microplasma generated with laser pulse energy of 65 mJ. The plot is obtained through spline interpolation of the Fourier transform of ten THz waveforms recorded at different detection angles in 10° intervals starting from 0°. All the spectra are normalized to one to show how the spectrum does not change appreciably with detection angle. However, by doing so the reader could be lead to believe that there is a strong emission for detection angle close to 0°. This is not the case as the amplitude of the spectra measured at 0° and 10° are more than one order of magnitude lower than those measured at larger angles
Fig.12  Peak amplitude of measured THz waveforms as a function of the azimuthal angle HWP placed in the laser beam path right before the microscope objective. The amplitude does not change upon linear rotations of the laser polarization
Fig.13  (a) THz waveforms measured when the laser beam has the following polarizations: linear (blue), circular (red), vortex (black), radial (magenta), azimuthal (green). (b) Comparison of the peak amplitudes obtained in the cases mentioned above
Fig.14  Parametric plot representing the measured polarization of the THz radiation in the case of p-polarized (red) and s-polarized (blue) laser beam. The polarization state of the collected THz wave does not change with the polarization of the laser beam
Fig.15  (a) THz peak power as a function of laser pulse energy for a detection angle of 80°. The laser source is Spectra Physics Hurricane (800 nm, 100 fs, 0.7 mJ, 1 kHz) and the microplasma is created with the 0.85 NA microscope objective. The dots are the experimental data, while the solid line is a quadratic fit. (b) THz peak power as a function of laser pulse energy for a detection angle of 80° (red). Fluorescence intensity integrated from 200 to 1000 nm as a function of laser pulse energy (gray).The laser source is Coherent Libra (800 nm, 50 fs, 50 fs, 1 kHz) and the microplasma is created with the 0.77 NA aspheric lens. The dots are the experimental data, while the solid line is a quadratic fit
Fig.16  THz pulse energy as a function of detection angle for microplasmas obtained with three different achromatic lenses: 0.77 NA (red); 0.68 NA (blue); 0.40 NA (black)
plasma length/mm peak emission angle/(° ) relative peak energy (normalized)
0.77 NA 72±8.3 70 1
0.68 NA 78±8.3 70 0.93
0.40 NA 120±8.3 50 0.74
Tab.3  Summary of the measurements of THz emission from microplasmas obtained with different focusing NA
Fig.17  (a) Experimental setup employing a parabolic reflector for the collection of the THz radiation emitted from the microplasma. (b) Diagram showing the transverse profile of the collimated THz beam exiting the parabolic reflector. The beam is radially polarized. (c) Zoom on the inside of the parabolic reflector showing how the THz radiation is collected. List of abbreviations: HWP, half wave plate; OBJ, objective; FM, flat mirror, OAPM, off-axis parabolic mirror; EOC, electro-optic crystal; EO DET, electro-optic detection
Fig.18  Comparison of THz waveforms obtained with a laser energy of 65 mJ with the following generation schemes: microplasma collected with the parabolic reflector (red); microplasma collected with the off-axis parabolic mirror (blue); two-color elongated plasma (black); one-color elongated plasma (green)
Fig.19  (a) Comparison of the spectrum obtained with a microplasma generated with 65 mJ laser energy (blue) with two-color elongated plasma generated with 102 mJ laser energy (gray). (b) Comparison of the spectrum obtained with a microplasma generated with 65 mJ laser energy (blue) with one-color elongated plasma generated with 214 mJ laser energy (green)
Fig.20  Experimental arrangement for the generation of the two-color microplasma
Fig.21  (a) Visible picture of the conical laser beam exiting the reflecting objective. The laser travels from left to right. The picture is obtained with a long exposure and by slowly moving a lens tissue along the laser propagation axis so to scatter light into the camera. (b) Transverse beam profile of the laser beam captured by a CCD camera at different distances from the focal plane z = 0
Fig.22  (a) THz pulse energy as a function of detection angle in the one-color (red) and two-color (blue) cases. In the one-color case the azimuthal angle of the b-BBO crystal is rotated so to minimize the SH emission, while in the two-color case so to maximize the THz wave emission. (b) Ratio of the THz peak fields in the two-color and one-color case as a function of detection angle (red). The dashed black line signaling a ratio equals to one is inserted as a reference
Fig.23  (a) THz peak amplitude as a function of the relative phase between FB and SH for the one-color (red) and two-color (blue) cases for different detection angles. The curves are offset for clarity. (b), (c) and (d) shows more clearly the experimental data for angle of 90°, 60°, and 30° respectively. Dots are experimental data, while blue line is the fitting of the two-color data with a sine function
Fig.24  Density plot representing the angle-dependent spectral emission from a microplasma generated with the reflective objective and laser pulse energy of 90 mJ. The plot is obtained through spline interpolation of the Fourier transform of ten THz waveforms recorded at different detection angles in 10° intervals starting from 0° obtained in the one-color (a) and two-color (b) cases. (c) Spectral amplitude measured at a detection angle of 60° in the one-color (red) and two-color (blue) cases. All the spectra are normalized to one to show how the spectrum does not change appreciably with detection angle. However, by doing so the reader could be lead to believe that there is a strong emission for detection angle close to 0°. This is not the case as the amplitude of the spectra measured at 0° and 10° are more than one order of magnitude lower than those measured at larger angles
Fig.25  Visual representation of the action of the ponderomotive force. The picture shows in red the intensity profile of a focused laser beam along the propagation axis and any radial direction. Charged particles close to the focal volume are pushed toward region of lower intensity
Fig.26  Longitudinal currents from which THz radiation originates is formed in a three steps process. (a) Electrons and ions are created at the front of the laser pulse; (b) Ions can be considered still due to their mass, while electrons are pushed backward from them by the ponderomotive force. The spatial separation between ions and electrons creates a net charge density behind the ionization front which acts as an effective dipole; (c) After the laser pulse leaves the plasma the charges are brought back together by the restoring force due to Coulomb attraction
Fig.27  Theoretical radiation pattern at a frequency of 1.5 THz of plasmas of lengths (a) 4 mm, (b) 400 mm and (c) 40 mm
Fig.28  Comparison of the radiation patterns calculated with numerical simulation and those measured experimentally. (a) one-color scheme, 40 mm plasma length: experiment (red solid), simulation (dashed, magenta); (b) one-color scheme, 72 mm plasma length (0.77 NA lens), red (simulation, dashed line, experiment, dots); 78 mm plasma length (0.68 NA lens), blue (simulation, dashed line, experiment, dots); 120 mm plasma length (0.40 NA lens), black (simulation, dashed line, experiment, dots); (c) two-color scheme, 40 μm plasma length (0.45 NA Schwarzschild reflective objective): one-color experiment (red, solid); one-color simulation (magenta, dashed); two-color experiment (blue, solid)
Fig.29  (a) Interaction geometries. Top: in copropagation geometry the THz (blue) and optical (red) pulses travel in the same direction. Dt is the time delay between the two. Bottom: in counter-propagation geometry the THz and pulses travel in opposite direction. In this case Dt defines the position along the optical propagation axis at which the THz and optical pulses meet. (b) Plasma fluorescence intensity enhancement as a function of Dt in copropagation (orange) and counter-propagation (blue) geometries. Both curves are normalized to one
Fig.30  Fluorescence intensity spectrum when no THz is applied (black) and for peak THz fields of 67 kV/cm (blue) and 90 kV/cm (red). The THz illuminates the plasma in counter-propagation geometry. All the emission lines belong to N2 2+ system. The numbers in parenthesis are the upper-lower vibrational levels of the transitions
Fig.31  (a) Experimental setup. The optical (red) and THz (blue) pulses travel in opposite direction. The plasma is imaged from the side with an iCCD camera through a narrowband filter centered at 337 nm. (b) Plasma fluorescence cross-sections with (blue) and without (dashed blue) THz illumination. The red curve is the spatially resolved fluorescence enhancement calculated by subtracting the fluorescence profile with and without THz illumination. (c) Spatially resolved fluorescence enhancement traces for different values of Dt. As Dt increases, the onset of the enhancement moves along the plasma toward the direction which the optical pulse comes from. (d) Plasma fluorescence intensity enhancement as a function of Dt in counter-propagation (blue) geometry. The colored points represent the area underneath the curves of (c) of the corresponding color and letter
Fig.32  Plasma fluorescence intensity enhancement as a function of Dt from plasmas obtained with the following optic components: 4 inch EFL plano-convex lens (blue); 2 inch EFL plano-convex lens (red); 1 inch EFL plano-convex lens (green); 0.14 NA microscope objective (purple). The plots are offset for clarity. Each trace in counter-propagation geometry is plotted together with the one in copropagation geometry obtained with the 4 inch EFL plano-convex lens (orange). Each curve is normalized to one
Fig.33  (a) and (b) Fluorescence intensity spectrum when no THz is applied (red) and peak THz field of 90 kV/cm (blue) for different values of laser energy. The microplasmas are obtained with (a) 1 inch EFL plano-convex lens and (b) the 0.14 NA microscope objective. (c) and (d) Plasma fluorescence intensity enhancement as a function of Dt for different values of laser energy. All curves are normalized to one. The microplasmas are obtained with (c) 1 inch EFL plano-convex lens (d) the 0.14 NA microscope objective
Fig.34  (a) Relative fluorescence enhancement as a function of laser energy for microplasmas obtained with 1 inch EFL plano-convex lens (red) and 0.14 NA microscope objective (green). (b) REEF figure of merit as a function of laser energy for microplasmas obtained with 1 inch EFL plano-convex lens (red) and 0.14 NA microscope objective (green)
copropagation counter-propagation
focusing
element
4 inches EFL
PC lens
4 inches EFL
PC lens
2 inches EFL
PC Lens
1 inch EFL
PC Lens
0.14 NA
objective
FOM 80.7 105.4 70.2 79.2 46.8
Tab.4  Comparison of the REEF traces obtained in copropagation and counter-propagation geometry through the REEF figure of merit (FOM)
Fig.35  Simulation of the REEF trace in copropagation geometry. The plot shows: the simulated plasma fluorescence intensity enhancement (black); the simulated THz waveform (red); the intensity as calculated by squaring the THz waveform (blue); the derivative of the plasma fluorescence intensity enhancement (fuchsia circles). The plasma fluorescence intensity enhancement curve and its derivative have been shifted of an amount tφ = 300 fs so to show the overlap of the second with the THz intensity curve
Fig.36  Experimental (solid line) and simulated (dashed line) plasma fluorescence intensity enhancement as a function of Dt in counter-propagation geometry for the following focusing conditions (a) 4 inches EFL PC lens; (b) 2 inches EFL PC lens; (c) 1 inches EFL PC lens; (d) 0.14 NA microscope objective
Fig.37  (a) Experimental plasma fluorescence intensity enhancement as a function of Dt in counter-propagation geometry for 2 inches EFL lens case (solid red) and its derivative (dashed red). The black dots represented the sampling points of the experimental data used to construct an interpolated curve of the measured data. The derivative of the interpolated curve is shown as a solid black curve. The curves are offset for clarity. (b) The derivative of the interpolated curve (solid black) is compared to the square of the experimental THz waveform measured with electro-optic sampling (solid blue)
Fig.38  Experimental (solid line) and numerical fitted (dashed line) plasma fluorescence intensity enhancement as a function of Dt in counter-propagation geometry for the following focusing conditions (a) 2 inches EFL PC lens; (c) 1 inches EFL PC lens; (e) 0.14 NA microscope objective. The respective electron densities are plotted in (b), (d) and (f). The solid lines represent the integration of the plasma fluorescence intensity along the radial dimension as measured with the iCCD camera, whereas the dashed line are the numerically evaluated plasma electron densities producing the curves plotted in (a), (c) and (e)
1 Nuss M C, Auston D H, Capasso F. Direct subpicosecond measurement of carrier mobility of photoexcited electrons in gallium arsenide. Physical Review Letters, 1987, 58(22): 2355–2358
https://doi.org/10.1103/PhysRevLett.58.2355 pmid: 10034724
2 Exter M, Fattinger C, Grischkowsky D. Terahertz time-domain spectroscopy of water vapor. Optics Letters, 1989, 14(20): 1128–1130
https://doi.org/10.1364/OL.14.001128 pmid: 19753077
3 Kolner B H, Buckles R A, Conklin P M, Scott R P. Plasma characterization with terahertz pulses. IEEE Journal of Selected Topics in Quantum Electronics, 2008, 14(2): 505–512
https://doi.org/10.1109/JSTQE.2007.913395
4 Jepsen P U, Cooke D G, Koch M. Terahertz spectroscopy and imaging- modern techniques and applications. Laser & Photonics Reviews, 2011, 5(1): 124–166
https://doi.org/10.1002/lpor.201000011
5 Ulbricht R, Hendry E, Shan J, Heinz T F, Bonn M. Carrier dynamics in semiconductors studied with time-resolved terahertz spectroscopy. Reviews of Modern Physics, 2011, 83(2): 543–586
https://doi.org/10.1103/RevModPhys.83.543
6 McIntosh A I, Yang B, Goldup S M, Watkinson M, Donnan R S. Terahertz spectroscopy: a powerful new tool for the chemical sciences? Chemical Society Reviews, 2012, 41(6): 2072–2082
https://doi.org/10.1039/C1CS15277G pmid: 22143259
7 Kübler C, Ehrke H, Huber R, Lopez R, Halabica A, Haglund R F Jr, Leitenstorfer A. Coherent structural dynamics and electronic correlations during an ultrafast insulator-to-metal phase transition in VO2. Physical Review Letters, 2007, 99(11): 116401
https://doi.org/10.1103/PhysRevLett.99.116401 pmid: 17930454
8 Leahy-Hoppa M R, Fitch M J, Zheng X, Hayden L M, Osiander R. Wideband terahertz spectroscopy of explosives. Chemical Physics Letters, 2007, 434(4-6): 227–230
https://doi.org/10.1016/j.cplett.2006.12.015
9 Davies A G, Burnett A D, Fan W, Linfield E H, Cunningham J E. Terahertz spectroscopy of explosives and drugs. Materials Today, 2008, 11(3): 18–26
https://doi.org/10.1016/S1369-7021(08)70016-6
10 Dai J, Xie X, Zhang X C. Detection of broadband terahertz waves with a laser-induced plasma in gases. Physical Review Letters, 2006, 97(10): 103903
https://doi.org/10.1103/PhysRevLett.97.103903 pmid: 17025819
11 Karpowicz N, Dai J, Lu X, Chen Y, Yamaguchi M, Zhao H, Zhang X C, Zhang L, Zhang C, Price-Gallagher M, Fletcher C, Mamer O, Lesimple A, Johnson K. Coherent heterodyne time-domain spectrometry covering the entire ‘terahertz gap’. Applied Physics Letters, 2008, 92(1): 011131
https://doi.org/10.1063/1.2828709
12 Liu J, Zhang X C. Birefringence and absorption coefficients of alpha barium borate in terahertz range. Journal of Applied Physics, 2009, 106(2): 023107
https://doi.org/10.1063/1.3176965
13 Zalkovskij M, Zoffmann Bisgaard C, Novitsky A, Malureanu R, Savastru D, Popescu A, Uhd Jepsen P, Lavrinenko A V. Ultrabroadband terahertz spectroscopy of chalcogenide glasses. Applied Physics Letters, 2012, 100(3): 031901
https://doi.org/10.1063/1.3676443
14 D’Angelo F, Mics Z, Bonn M, Turchinovich D. Ultra-broadband THz time-domain spectroscopy of common polymers using THz air photonics. Optics Express, 2014, 22(10): 12475–12485
https://doi.org/10.1364/OE.22.012475 pmid: 24921365
15 McLaughlin C V, Hayden L M, Polishak B, Huang S, Luo J, Kim T D, Jen A K Y. Wideband 15 THz response using organic electro-optic polymer emitter-sensor pairs at telecommunication wavelengths. Applied Physics Letters, 2008, 92(15): 151107
https://doi.org/10.1063/1.2909599
16 Seifert T, Jaiswal S, Martens U, Hannegan J, Braun L, Maldonado P, Freimuth F, Kronenberg A, Henrizi J, Radu I, Beaurepaire E, Mokrousov Y, Oppeneer P M, Jourdan M, Jakob G, Turchinovich D, Hayden L M, Wolf M, Münzenberg M, Kläui M, Kampfrath T. Efficient metallic spintronic emitters of ultrabroadband terahertz radiation. Nature Photonics, 2016, 10(7): 483–488
https://doi.org/10.1038/nphoton.2016.91
17 Clough B, Dai J, Zhang X C. Laser air photonics: beyond the terahertz gap. Materials Today, 2012, 15(1-2): 50–58
https://doi.org/10.1016/S1369-7021(12)70020-2
18 Chen Y, Yamaguchi M, Wang M, Zhang X C. Terahertz pulse generation from noble gases. Applied Physics Letters, 2007, 91(25): 251116
https://doi.org/10.1063/1.2826544
19 Lu X, Karpowicz N, Chen Y, Zhang X C. Systematic study of broadband terahertz gas sensor. Applied Physics Letters, 2008, 93(26): 261106
https://doi.org/10.1063/1.3056119
20 Kress M, Löffler T, Eden S, Thomson M, Roskos H G. Terahertz-pulse generation by photoionization of air with laser pulses composed of both fundamental and second-harmonic waves. Optics Letters, 2004, 29(10): 1120–1122
https://doi.org/10.1364/OL.29.001120 pmid: 15182005
21 Xie X, Dai J, Zhang X C. Coherent control of THz wave generation in ambient air. Physical Review Letters, 2006, 96(7): 075005
https://doi.org/10.1103/PhysRevLett.96.075005 pmid: 16606102
22 Leisawitz D T, Danchi W C, DiPirro M J, Feinberg L D, Gezari D Y, Hagopian M, Langer W D, Mather J C, Moseley S H, Shao M, Silverberg R F, Staguhn J G, Swain M R, Yorke H W, Zhang X L. Scientific motivation and technology requirements for the SPIRIT and SPECS far-infrared/submillimeter space interferometers. In: Proceedings of SPIE 4013, UV, Optical, and IR Space Telescopes and Instruments. Munich, Germany: SPIE, 2000, 36–46 doi:10.1117/12.393957
23 Ferguson B, Zhang X C. Materials for terahertz science and technology. Nature Materials, 2002, 1(1): 26–33
https://doi.org/10.1038/nmat708 pmid: 12618844
24 Siegel P H. Terahertz technology. IEEE Transactions on Microwave Theory and Techniques, 2002, 50(3): 910–928
https://doi.org/10.1109/22.989974
25 Tonouchi M. Cutting-edge terahertz technology. Nature Photonics, 2007, 1(2): 97–105
https://doi.org/10.1038/nphoton.2007.3
26 Kimmitt M F. Restrahlen to T-rays - 100 years of terahertz radiation. Journal of Biological Physics, 2003, 29(2–3): 77–85
https://doi.org/10.1023/A:1024498003492 pmid: 23345821
27 Siegel P H. Terahertz pioneer: David H. Auston. IEEE Transactions on Terahertz Science and Technology, 2011, 1(1): 6–8
https://doi.org/10.1109/TTHZ.2011.2151130
28 Siegel P H. Terahertz pioneer: Maurice F. Kimmitt ‘A Person Who Makes Things Work’. IEEE Transactions on Terahertz Science and Technology, 2012, 2(1): 6–9
https://doi.org/10.1109/TTHZ.2011.2178654
29 Siegel P H. Terahertz pioneer: Thomas G. Phillips ‘The Sky Above, the Mountain Below’. IEEE Transactions on Terahertz Science and Technology, 2012, 2(5): 478–484
https://doi.org/10.1109/TTHZ.2012.2211353
30 Siegel P H. Terahertz pioneer: Frank C. De Lucia ‘The Numbers Count’. IEEE Transactions on Terahertz Science and Technology, 2012, 2(6): 578–583
https://doi.org/10.1109/TTHZ.2012.2222638
31 Siegel P H. Terahertz pioneer: Richard J. Saykally - water, water everywhere..... IEEE Transactions on Terahertz Science and Technology, 2012, 2(3): 266–270
https://doi.org/10.1109/TTHZ.2012.2190870
32 Siegel P H. Terahertz pioneer: Robert W. Wilson the foundations of THz radio science. IEEE Transactions on Terahertz Science and Technology, 2012, 2(2): 162–166
https://doi.org/10.1109/TTHZ.2011.2182390
33 Siegel P H. Terahertz pioneer: Daniel R. Grischkowsky ‘We Search for Truth and Beauty’. IEEE Transactions on Terahertz Science and Technology, 2012, 2(4): 378–382
https://doi.org/10.1109/TTHZ.2012.2198216
34 Siegel P H. Terahertz pioneers: Manfred Winnewisser and Brenda PrudenWinnewisser: ‘Equating Hamiltonians to nature’. IEEE Transactions on Terahertz Science and Technology, 2013, 3(3): 229–236
https://doi.org/10.1109/TTHZ.2013.2256392
35 Siegel P H. Terahertz pioneer: Sir John B. Pendry ‘Theoretical Physics for a Practical World’. IEEE Transactions on Terahertz Science and Technology, 2013, 3(6): 693–701
https://doi.org/10.1109/TTHZ.2013.2285322
36 Siegel P H. Terahertz pioneer: Philippe Goy “If You Agree with the Majority, You Might be Wrong”. IEEE Transactions on Terahertz Science and Technology, 2013, 3(4): 348–353
https://doi.org/10.1109/TTHZ.2013.2260373
37 Siegel P H. Terahertz pioneer: Federico Capasso “Physics by Design: Engineering Our Way Out of the THz Gap”. IEEE Transactions on Terahertz Science and Technology, 2013, 3(1): 6–13
https://doi.org/10.1109/TTHZ.2013.2238631
38 Siegel P H. Terahertz pioneer: Fritz Keilmann- ‘RF Biophysics: From strong field to near field’. IEEE Transactions on Terahertz Science and Technology, 2013, 3(5): 506–514
https://doi.org/10.1109/TTHZ.2013.2272656
39 Siegel P H. Terahertz pioneer: Koji Mizuno ‘50 Years in Submillimeter-Waves: From Otaku to Sensei’. IEEE Transactions on Terahertz Science and Technology, 2013, 3(2): 130–133
https://doi.org/10.1109/TTHZ.2013.2245178
40 Siegel P H. Terahertz pioneer: Erik L. Kollberg ‘Instrument Maker to the Stars’. IEEE Transactions on Terahertz Science and Technology, 2014, 4(5): 538–544
https://doi.org/10.1109/TTHZ.2014.2344191
41 Siegel P H. Terahertz pioneer: Michael Bass ‘The THz Light at the End of the Tunnel’. IEEE Transactions on Terahertz Science and Technology, 2014, 4(4): 410–417
https://doi.org/10.1109/TTHZ.2014.2326300
42 Siegel P H. Terahertz pioneer: Shenggang Liu ‘China’s Father of Vacuum and Microwave Electronics’. IEEE Transactions on Terahertz Science and Technology, 2014, 4(1): 6–11
https://doi.org/10.1109/TTHZ.2013.2294760
43 Siegel P H. Terahertz pioneer: Mattheus (Thijs) de Graauw ‘Intention, Attention, Execution’. IEEE Transactions on Terahertz Science and Technology, 2014, 4(2): 138–146
https://doi.org/10.1109/TTHZ.2014.2304671
44 Siegel P H. Terahertz pioneer: Robert J. Mattauch “Two Terminals Will Suffice”. IEEE Transactions on Terahertz Science and Technology, 2014, 4(6): 646–652
https://doi.org/10.1109/TTHZ.2014.2361256
45 Siegel P H. Terahertz pioneer: Tatsuo Itoh ‘Transmission Lines and Antennas: Left and Right’. IEEE Transactions on Terahertz Science and Technology, 2014, 4(3): 298–306
https://doi.org/10.1109/TTHZ.2014.2312852
46 Siegel P H. Terahertz pioneer: Xi-Cheng Zhang ‘The Face of THz’. IEEE Transactions on Terahertz Science and Technology, 2015, 5(5): 706–714
https://doi.org/10.1109/TTHZ.2015.2462123
47 Phillips T G, Keene J. Submillimeter astronomy (heterodyne spectroscopy). Proceedings of the IEEE, 1992, 80(11): 1662–1678
https://doi.org/10.1109/5.175248
48 Siegel P H, Pikov V. Impact of low intensity millimetre waves on cell functions. Electronics Letters, 2010, 46(26): S70
https://doi.org/10.1049/el.2010.8442
49 Alexandrov B S, Gelev V, Bishop A R, Usheva A, Rasmussen K O. DNA breathing dynamics in the presence of a terahertz field. Physics Letters A, 2010, 374(10): 1214–1217
https://doi.org/10.1016/j.physleta.2009.12.077 pmid: 20174451
50 Yang Y, Mandehgar M, Grischkowsky D R. Broadband THz pulse transmission through the atmosphere. IEEE Transactions on Terahertz Science and Technology, 2011, 1(1): 264–273
https://doi.org/10.1109/TTHZ.2011.2159554
51 Svelto O, Hanna D C. Principles of Lasers. Boston, MA: Springer, 2009
52 Wu Z, Fisher A S, Goodfellow J, Fuchs M, Daranciang D, Hogan M, Loos H, Lindenberg A. Intense terahertz pulses from SLAC electron beams using coherent transition radiation. Review of Scientific Instruments, 2013, 84(2): 022701
https://doi.org/10.1063/1.4790427 pmid: 23464183
53 Elias L R, Hu J, Ramian G. The UCSB electrostatic accelerator free electron laser: first operation. Nuclear Instruments & Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment, 1985, 237(1-2): 203–206
https://doi.org/10.1016/0168-9002(85)90349-3
54 Reimann K. Table-top sources of ultrashort THz pulses. Reports on Progress in Physics, 2007, 70(10): 1597–1632
https://doi.org/10.1088/0034-4885/70/10/R02
55 Kitaeva G K. Terahertz generation by means of optical lasers. Laser Physics Letters, 2008, 5(8): 559–576
https://doi.org/10.1002/lapl.200810039
56 Hebling J, Yeh K L, Hoffmann M C, Bartal B, Nelson K A. Generation of high-power terahertz pulses by tilted-pulse-front excitation and their application possibilities. Journal of the Optical Society of America. B, Optical Physics, 2008, 25(7): B6
https://doi.org/10.1364/JOSAB.25.0000B6
57 Rice A, Jin Y, Ma X F, Zhang X C, Bliss D, Larkin J, Alexander M. Terahertz optical rectification from 〈110〉 zinc-blende crystals. Applied Physics Letters, 1994, 64(11): 1324–1326
https://doi.org/10.1063/1.111922
58 Fülöp J A, Pálfalvi L, Klingebiel S, Almási G, Krausz F, Karsch S, Hebling J. Generation of sub-mJ terahertz pulses by optical rectification. Optics Letters, 2012, 37(4): 557–559
https://doi.org/10.1364/OL.37.000557 pmid: 22344105
59 Shalaby M, Hauri C P. Demonstration of a low-frequency three-dimensional terahertz bullet with extreme brightness. Nature Communications, 2015, 6(1): 5976
https://doi.org/10.1038/ncomms6976 pmid: 25591665
60 Hirori H, Doi A, Blanchard F, Tanaka K. Single-cycle terahertz pulses with amplitudes exceeding 1 MV/cm generated by optical rectification in LiNbO3. Applied Physics Letters, 2011, 98(9): 091106
https://doi.org/10.1063/1.3560062
61 Auston D H. Picosecond optoelectronic switching and gating in silicon. Applied Physics Letters, 1975, 26(3): 101–103
https://doi.org/10.1063/1.88079
62 Mourou G, Stancampiano C V, Antonetti A, Orszag A. Picosecond microwave pulses generated with a subpicosecond laser-driven semiconductor switch. Applied Physics Letters, 1981, 39(4): 295–296
https://doi.org/10.1063/1.92719
63 Budiarto E, Margolies J, Jeong S, Son J, Bokor J. High-intensity terahertz pulses at 1-kHz repetition rate. IEEE Journal of Quantum Electronics, 1996, 32(10): 1839–1846
https://doi.org/10.1109/3.538792
64 Look D C. Molecular beam epitaxial GaAs grown at low temperatures. Thin Solid Films, 1993, 231(1-2): 61–73
https://doi.org/10.1016/0040-6090(93)90703-R
65 Beard M C, Turner G M, Schmuttenmaer C A. Subpicosecond carrier dynamics in low-temperature grown GaAs as measured by time-resolved terahertz spectroscopy. Journal of Applied Physics, 2001, 90(12): 5915–5923
https://doi.org/10.1063/1.1416140
66 Richards P L. Bolometers for infrared and millimeter waves. Journal of Applied Physics, 1994, 76(1): 1–24
https://doi.org/10.1063/1.357128
67 Mauskopf P D, Bock J J, Del Castillo H, Holzapfel W L, Lange A E. Composite infrared bolometers with Si3N4 micromesh absorbers. Applied Optics, 1997, 36(4): 765–771
https://doi.org/10.1364/AO.36.000765 pmid: 18250736
68 Nahum M, Martinis J M. Ultrasensitive-hot-electron microbolometer. Applied Physics Letters, 1993, 63(22): 3075–3077
https://doi.org/10.1063/1.110237
69 Golay M J E. A pneumatic infra-red detector. Review of Scientific Instruments, 1947, 18(5): 357–362
https://doi.org/10.1063/1.1740949 pmid: 20245300
70 Gautschi G. Piezoelectric Sensorics: Force, Strain, Pressure, Acceleration and Acoustic Emission Sensors, Materials and Amplifiers. Berlin, Heidelberg: Springer, 2002
71 Komiyama S, Astafiev O, Antonov V, Kutsuwa T, Hirai H. A single-photon detector in the far-infrared range. Nature, 2000, 403(6768): 405–407
https://doi.org/10.1038/35000166 pmid: 10667787
72 Kim K T, Zhang C, Shiner A D, Schmidt B E, Légaré F, Villeneuve D M, Corkum P B. Petahertz optical oscilloscope. Nature Photonics, 2013, 7(12): 958–962
https://doi.org/10.1038/nphoton.2013.286
73 Teo S M, Ofori-Okai B K, Werley C A, Nelson K A. Single-shot THz detection techniques optimized for multidimensional THz spectroscopy. Review of Scientific Instruments, 2015, 86(5): 051301
https://doi.org/10.1063/1.4921389 pmid: 26026507
74 Wu Q, Zhang X C. Free-space electro-optic sampling of terahertz beams. Applied Physics Letters, 1995, 67(24): 3523–3525
https://doi.org/10.1063/1.114909
75 Leitenstorfer A, Hunsche S, Shah J, Nuss M C, Knox W H. Detectors and sources for ultrabroadband electro-optic sampling: experiment and theory. Applied Physics Letters, 1999, 74(11): 1516–1518
https://doi.org/10.1063/1.123601
76 Auston D H, Smith P R. Generation and detection of millimeter waves by picosecond photoconductivity. Applied Physics Letters, 1983, 43(7): 631–633
https://doi.org/10.1063/1.94468
77 Grischkowsky D, Keiding S, van Exter M, Fattinger C. Far-infrared time-domain spectroscopy with terahertz beams of dielectrics and semiconductors. Journal of the Optical Society of America. B, Optical Physics, 1990, 7(10): 2006
https://doi.org/10.1364/JOSAB.7.002006
78 Wu Q, Hewitt T D, Zhang X C. Two-dimensional electro-optic imaging of THz beams. Applied Physics Letters, 1996, 69(8): 1026–1028
https://doi.org/10.1063/1.116920
79 Mittleman D M, Jacobsen R H, Nuss M C. T-ray imaging. IEEE Journal of Selected Topics in Quantum Electronics, 1996, 2(3): 679–692
https://doi.org/10.1109/2944.571768
80 Mittleman D M, Hunsche S, Boivin L, Nuss M C. T-ray tomography. Optics Letters, 1997, 22(12): 904–906
https://doi.org/10.1364/OL.22.000904 pmid: 18185701
81 Woodward R M, Cole B E, Wallace V P, Pye R J, Arnone D D, Linfield E H, Pepper M. Terahertz pulse imaging in reflection geometry of human skin cancer and skin tissue. Physics in Medicine and Biology, 2002, 47(21): 3853–3863
https://doi.org/10.1088/0031-9155/47/21/325 pmid: 12452577
82 Seco-Martorell C, López-Domínguez V, Arauz-Garofalo G, Redo-Sanchez A, Palacios J, Tejada J. Goya’s artwork imaging with Terahertz waves. Optics Express, 2013, 21(15): 17800–17805
https://doi.org/10.1364/OE.21.017800 pmid: 23938652
83 Zhong H, Xu J Z, Xie X, Yuan T, Reightler R, Madaras E, Zhang X C. Nondestructive defect identification with terahertz time-of-flight tomography. IEEE Sensors Journal, 2005, 5(2): 203–208
https://doi.org/10.1109/JSEN.2004.841341
84 Beard M C, Turner G M, Schmuttenmaer C A. Terahertz Spectroscopy. Journal of Physical Chemistry B, 2002, 106(29): 7146–7159
https://doi.org/10.1021/jp020579i
85 Sell A, Leitenstorfer A, Huber R. Phase-locked generation and field-resolved detection of widely tunable terahertz pulses with amplitudes exceeding 100 MV/cm. Optics Letters, 2008, 33(23): 2767–2769
https://doi.org/10.1364/OL.33.002767 pmid: 19037420
86 Kampfrath T, Tanaka K, Nelson K A. Resonant and nonresonant control over matter and light by intense terahertz transients. Nature Photonics, 2013, 7(9): 680–690
https://doi.org/10.1038/nphoton.2013.184
87 Schubert O, Hohenleutner M, Langer F, Urbanek B, Lange C, Huttner U, Golde D, Meier T, Kira M, Koch S W, Huber R. Sub-cycle control of terahertz high-harmonic generation by dynamical Bloch oscillations. Nature Photonics, 2014, 8(2): 119–123
https://doi.org/10.1038/nphoton.2013.349
88 Hamster H, Sullivan A, Gordon S, White W, Falcone R W. Subpicosecond, electromagnetic pulses from intense laser-plasma interaction. Physical Review Letters, 1993, 71(17): 2725–2728
https://doi.org/10.1103/PhysRevLett.71.2725 pmid: 10054760
89 Löffler T, Jacob F, Roskos H G. Generation of terahertz pulses by photoionization of electrically biased air. Applied Physics Letters, 2000, 77(3): 453–455
https://doi.org/10.1063/1.127007
90 Cook D J, Hochstrasser R M. Intense terahertz pulses by four-wave rectification in air. Optics Letters, 2000, 25(16): 1210–1212
https://doi.org/10.1364/OL.25.001210 pmid: 18066171
91 Liu J, Zhang X C. Terahertz-radiation-enhanced emission of fluorescence from gas plasma. Physical Review Letters, 2009, 103(23): 235002
https://doi.org/10.1103/PhysRevLett.103.235002 pmid: 20366153
92 Clough B, Liu J, Zhang X C. Laser-induced photoacoustics influenced by single-cycle terahertz radiation. Optics Letters, 2010, 35(21): 3544–3546
https://doi.org/10.1364/OL.35.003544 pmid: 21042344
93 Hamster H, Sullivan A, Gordon S, Falcone R W. Short-pulse terahertz radiation from high-intensity-laser-produced plasmas. Physical Review E: Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, 1994, 49(1): 671–677
https://doi.org/10.1103/PhysRevE.49.671 pmid: 9961261
94 Durand M, Houard A, Prade B, Mysyrowicz A, Durécu A, Moreau B, Fleury D, Vasseur O, Borchert H, Diener K, Schmitt R, Théberge F, Chateauneuf M, Daigle J F, Dubois J. Kilometer range filamentation. Optics Express, 2013, 21(22): 26836–26845
https://doi.org/10.1364/OE.21.026836 pmid: 24216905
95 D’Amico C, Houard A, Franco M, Prade B, Mysyrowicz A, Couairon A, Tikhonchuk V T. Conical forward THz emission from femtosecond-laser-beam filamentation in air. Physical Review Letters, 2007, 98(23): 235002
https://doi.org/10.1103/PhysRevLett.98.235002 pmid: 17677911
96 Houard A, Liu Y, Prade B, Tikhonchuk V T, Mysyrowicz A. Strong enhancement of terahertz radiation from laser filaments in air by a static electric field. Physical Review Letters, 2008, 100(25): 255006
https://doi.org/10.1103/PhysRevLett.100.255006 pmid: 18643672
97 Liu Y, Houard A, Prade B, Mysyrowicz A, Diaw A, Tikhonchuk V T. Amplification of transition-Cherenkov terahertz radiation of femtosecond filament in air. Applied Physics Letters, 2008, 93(5): 051108
https://doi.org/10.1063/1.2965612
98 Mitryukovskiy S I, Liu Y, Prade B, Houard A, Mysyrowicz A. Coherent synthesis of terahertz radiation from femtosecond laser filaments in air. Applied Physics Letters, 2013, 102(22): 221107
https://doi.org/10.1063/1.4807917
99 Kim K Y, Glownia J H, Taylor A J, Rodriguez G. Terahertz emission from ultrafast ionizing air in symmetry-broken laser fields. Optics Express, 2007, 15(8): 4577–4584
https://doi.org/10.1364/OE.15.004577 pmid: 19532704
100 Karpowicz N, Zhang X C. Coherent terahertz echo of tunnel ionization in gases. Physical Review Letters, 2009, 102(9): 093001
https://doi.org/10.1103/PhysRevLett.102.093001 pmid: 19392516
101 Bergé L, Skupin S, Köhler C, Babushkin I, Herrmann J. 3D numerical simulations of THz generation by two-color laser filaments. Physical Review Letters, 2013, 110(7): 073901
https://doi.org/10.1103/PhysRevLett.110.073901 pmid: 25166373
102 Clerici M, Peccianti M, Schmidt B E, Caspani L, Shalaby M, Giguère M, Lotti A, Couairon A, Légaré F, Ozaki T, Faccio D, Morandotti R. Wavelength scaling of terahertz generation by gas ionization. Physical Review Letters, 2013, 110(25): 253901
https://doi.org/10.1103/PhysRevLett.110.253901 pmid: 23829737
103 Oh T I, Yoo Y J, You Y S, Kim K Y. Generation of strong terahertz fields exceeding 8 MV/cm at 1 kHz and real-time beam profiling. Applied Physics Letters, 2014, 105(4): 041103
https://doi.org/10.1063/1.4891678
104 Thomson M D, Blank V, Roskos H G. Terahertz white-light pulses from an air plasma photo-induced by incommensurate two-color optical fields. Optics Express, 2010, 18(22): 23173–23182
https://doi.org/10.1364/OE.18.023173 pmid: 21164658
105 Dai J, Zhang X C. Terahertz wave generation from gas plasma using a phase compensator with attosecond phase-control accuracy. Applied Physics Letters, 2009, 94(2): 021117
https://doi.org/10.1063/1.3068501
106 Wen H, Lindenberg A M. Coherent terahertz polarization control through manipulation of electron trajectories. Physical Review Letters, 2009, 103(2): 023902
https://doi.org/10.1103/PhysRevLett.103.023902 pmid: 19659205
107 Dai J, Karpowicz N, Zhang X C. Coherent polarization control of terahertz waves generated from two-color laser-induced gas plasma. Physical Review Letters, 2009, 103(2): 023001
https://doi.org/10.1103/PhysRevLett.103.023001 pmid: 19659200
108 Zhong H, Karpowicz N, Zhang X C. Terahertz emission profile from laser-induced air plasma. Applied Physics Letters, 2006, 88(26): 261103
https://doi.org/10.1063/1.2216025
109 Klarskov P, Strikwerda A C, Iwaszczuk K, Jepsen P U. Experimental three-dimensional beam profiling and modeling of a terahertz beam generated from a two-color air plasma. New Journal of Physics, 2013, 15(7): 075012
https://doi.org/10.1088/1367-2630/15/7/075012
110 Blank V, Thomson M D, Roskos H G. Spatio-spectral characteristics of ultra-broadband THz emission from two-colourphotoexcited gas plasmas and their impact for nonlinear spectroscopy. New Journal of Physics, 2013, 15(7): 075023
https://doi.org/10.1088/1367-2630/15/7/075023
111 You Y S, Oh T I, Kim K Y. Off-axis phase-matched terahertz emission from two-color laser-induced plasma filaments. Physical Review Letters, 2012, 109(18): 183902
https://doi.org/10.1103/PhysRevLett.109.183902 pmid: 23215280
112 Gorodetsky A, Koulouklidis A D, Massaouti M, Tzortzakis S. Physics of the conical broadband terahertz emission from two-color laser-induced plasma filaments. Physical Review A., 2014, 89(3): 033838
https://doi.org/10.1103/PhysRevA.89.033838
113 Wang T J, Yuan S, Chen Y, Daigle J F, Marceau C, Théberge F, Châteauneuf M, Dubois J, Chin S L. Toward remote high energy terahertz generation. Applied Physics Letters, 2010, 97(11): 111108
https://doi.org/10.1063/1.3490702
114 Wang T J, Daigle J F, Yuan S, Théberge F, Châteauneuf M, Dubois J, Roy G, Zeng H, Chin S L. Remote generation of high-energy terahertz pulses from two-color femtosecond laser filamentation in air. Physical Review A., 2011, 83(5): 053801
https://doi.org/10.1103/PhysRevA.83.053801
115 Nahata A, Heinz T F. Detection of freely propagating terahertz radiation by use of optical second-harmonic generation. Optics Letters, 1998, 23(1): 67–69
https://doi.org/10.1364/OL.23.000067 pmid: 18084414
116 Liu J, Zhang X C. Enhancement of laser-induced fluorescence by intense terahertz pulses in gases. IEEE Journal of Selected Topics in Quantum Electronics, 2011, 17(1): 229–236
https://doi.org/10.1109/JSTQE.2010.2046142
117 Liu J, Dai J, Zhang X C. Ultrafast broadband terahertz waveform measurement utilizing ultraviolet plasma photoemission. Journal of the Optical Society of America B, Optical Physics, 2011, 28(4): 796
https://doi.org/10.1364/JOSAB.28.000796
118 Liu J, Dai J, Chin S L, Zhang X C. Broadband terahertz wave remote sensing using coherent manipulation of fluorescence from asymmetrically ionized gases. Nature Photonics, 2010, 4(9): 627–631
https://doi.org/10.1038/nphoton.2010.165
119 Clough B, Liu J, Zhang X C. “All air-plasma” terahertz spectroscopy. Optics Letters, 2011, 36(13): 2399–2401
https://doi.org/10.1364/OL.36.002399 pmid: 21725424
120 Maker P D, Terhune R W, Savage C M. Optical third harmonic generation. In: Proceedings of the 3rd International Congress, Quantum Electron. Paris: Dunod Éditeur, 1964, 1559
121 Talebpour A, Yang J, Chin S L. Semi-empirical model for the rate of tunnel ionization of N2 and O2 molecule in an intense Ti:sapphire laser pulse. Optics Communications, 1999, 163(1-3): 29–32
https://doi.org/10.1016/S0030-4018(99)00113-3
122 Couairon A, Mysyrowicz A. Femtosecond filamentation in transparent media. Physics Reports, 2007, 441(2-4): 47–189
https://doi.org/10.1016/j.physrep.2006.12.005
123 Chin S L. Femtosecond Laser Filamentation. New York: Springer, 2010
124 Abdollahpour D, Suntsov S, Papazoglou D G, Tzortzakis S. Measuring easily electron plasma densities in gases produced by ultrashort lasers and filaments. Optics Express, 2011, 19(18): 16866–16871
https://doi.org/10.1364/OE.19.016866 pmid: 21935047
125 Arévalo E, Becker A. Theoretical analysis of fluorescence signals in filamentation of femtosecond laser pulses in nitrogen molecular gas. Physical Review A., 2005, 72(4): 043807
https://doi.org/10.1103/PhysRevA.72.043807
126 Talebpour A, Petit S, Chin S. Re-focusing during the propagation of a focused femtosecond Ti:Sapphire laser pulse in air. Optics Communications, 1999, 171(4-6): 285–290
https://doi.org/10.1016/S0030-4018(99)00498-8
127 Bukin V V, Vorob’ev N S, Garnov S V, Konov V I, Lozovoi V I, Malyutin A A, Shchelev M Y, Yatskovskii I S. Formation and development dynamics of femtosecond laser microplasma in gases. Quantum Electronics, 2006, 36(7): 638–645
https://doi.org/10.1070/QE2006v036n07ABEH013173
128 Martin F, Mawassi R, Vidal F, Gallimberti I, Comtois D, Pépin H, Kieffer J C, Mercure H P. Spectroscopic study of ultrashort pulse laser-breakdown plasmas in air. Applied Spectroscopy, 2002, 56(11): 1444–1452
https://doi.org/10.1366/00037020260377742
129 Herzberg G. Molecular Spectra and Molecular Structure. Malabar, FL: R.E. Krieger Pub. Co, 1989
130 Becker A, Bandrauk A D, Chin S L. S-matrix analysis of non-resonant multiphoton ionisation of inner-valence electrons of the nitrogen molecule. Chemical Physics Letters, 2001, 343(3-4): 345–350
https://doi.org/10.1016/S0009-2614(01)00705-9
131 Xu H L, Azarm A, Bernhardt J, Kamali Y, Chin S L. The mechanism of nitrogen fluorescence inside a femtosecond laser filament in air. Chemical Physics, 2009, 360(1-3): 171–175
https://doi.org/10.1016/j.chemphys.2009.05.001
132 Vidal F, Comtois D, Chien C Y, Desparois A, La Fontaine B, Johnston T W, Kieffer J C, Mercure H P, Pepin H, Rizk F A. Modeling the triggering of streamers in air by ultrashort laser pulses. IEEE Transactions on Plasma Science, 2000, 28(2): 418–433
https://doi.org/10.1109/27.848101
133 Sato M, Higuchi T, Kanda N, Konishi K, Yoshioka K, Suzuki T, Misawa K, Kuwata-Gonokami M. Terahertz polarization pulse shaping with arbitrary field control. Nature Photonics, 2013, 7(9): 724–731
https://doi.org/10.1038/nphoton.2013.213
134 Amico C D, Houard A, Akturk S, Liu Y, Le Bloas J, Franco M, Prade B, Couairon A, Tikhonchuk V T, Mysyrowicz A. Forward THz radiation emission by femtosecond filamentation in gases: theory and experiment. New Journal of Physics, 2008, 10(1): 013015
https://doi.org/10.1088/1367-2630/10/1/013015
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