Laser cooling of internal degrees of freedom of molecules

Abstract

Optical pumping techniques using laser fields combined with photo-association of ultracold atoms leads to control of the vibrational and/or rotational population of molecules. In this study, we review the basic concepts and main steps that should be followed, including the excitation schemes and detection techniques used to achieve ro-vibrational cooling of Cs₂ molecules. We also discuss the extension of this technique to other molecules. In addition, we present a theoretical model used to support the experiment. These simulations can be widely used for the preparation of various experiments because they allow the optimization of several important experimental parameters.

Keywords

cold molecule / photo-association / optical pumping / vibrational and rotational cooling

References

[1] L. D. Carr, D. DeMille, R. V. Krems, and J. Ye, Cold and ultracold molecules: Science, technology and applications, New J. Phys. 11(5), 055049 (2009)

[2] J. J. Hudson, D. M. Kara, I. J. Smallman, B. E. Sauer, M. R. Tarbutt, and E. A. Hinds, Improved measurement of the shape of the electron, Nature 473, 493 (2011)

[3] D. S. Jin and J. Ye, Introduction to ultracold molecules: New frontiers in quantum and chemical physics, Chem. Rev. 112(9), 4801 (2012)

[4] M. Shapiro and P. Brumer, Principles of the Quantum Control of Molecular Processes, Wiley-Interscience, NJ: Hoboken, 2003

[5] D. D'Alessandro, Introduction to Quantum Control and Dynamics, Boca Raton: Chapman and Hall, 2007

[6] G. Quéméner and P. S.Julienne, Ultracold molecules under control! Chem. Rev. 112(9), 4949 (2012)

[7] G. Morigi, P. W. H. Pinkse, M. Kowalewski, and R. de Vivie-Riedle, Cavity cooling of internal molecular motion, Phys. Rev. Lett. 99(7), 073001 (2007)

[8] D. J. Tannor, R. Kosloff, and A. Bartana, Laser cooling of internal degrees of freedom of molecules by dynamically trapped states, Faraday Discuss. 113, 365 (1999)

[9] S. G. Schirmer, Laser cooling of internal molecular degrees of freedom for vibrationally hot molecules, Phys. Rev. A 63(1), 013407 (2000)

[10] A. Bartana, R. Kosloff, and D. J. Tannor, Laser cooling of molecular internal degrees of freedom by a series of shaped pulses, J. Chem. Phys. 99(1), 196 (1993)

[11] S. A. Rice, A. R. Dinner, C. Brif, R. Chakrabarti, and H. Rabitz, Adv. Chem. Phys. 148, edited by S. A. Rice and A. R. Dinner, Wiley, 2011

[12] E. Shuman, J. Barry, and D. DeMille, Laser cooling of a diatomic molecule, Nature 467(7317), 820 (2010)

[13] J. F. Barry, E. S. Shuman, E. B. Norrgard, and D. De-Mille, Laser radiation pressure slowing of a molecular beam, Phys. Rev. Lett. 108(10), 103002 (2012)

[14] M. T. Hummon, M. Yeo, B. K. Stuhl, A. L. Collopy, Y. Xia, and J. Ye, Magneto-optical trapping of diatomic molecules, arXiv: 1209.4069v1

[15] M. Zeppenfeld, B. G. U. Englert, R. Glöckner, A. Prehn, M. Mielenz, C. Sommer, L. D. van Buuren, M. Motsch, and G. Rempe, Sisyphus cooling of electrically trapped polyatomic molecules, Nature 491(7425), 570 (2012)

[16] J. G. Danzl, M. J. Mark, E. Haller, M. Gustavsson, R. Hart, J. Aldegunde, J. M. Hutson, and H.C. Nägerl, An ultracold high-density sample of rovibronic ground-state molecules in an optical lattice, Nat. Phys. 6(4), 265 (2010)

[17] S. Ospelkaus, K.-K. Ni, G. Quéméner, B. Neyenhuis, D. Wang, M. H. G. de Miranda, J. L. Bohn, J. Ye, and D. S. Jin, Controlling the hyperfine state of rovibronic ground-state polar molecules, Phys. Rev. Lett. 104, 030402 (2010), arXiv: 0908.3931

[18] G. Pichler, S. Milosevic, D. Viza, and R. Beuc, Diffuse bands in the visible absorption spectra of dense alkali vapours, J. Phys. At. Mol. Opt. Phys. 16(24), 4619 (1983)

[19] R. B. Jones, J. H. Schloss, and J. G. Eden, Excitation spectra for the photoassociation of Kr–F and Xe–I collision pairs in the ultraviolet (208–258 nm), J. Chem. Phys. 98(6), 4317 (1993)

[20] U. Marvet and M. Dantus, Femtosecond photoassociation spectroscopy: Coherent bond formation, Chem. Phys. Lett. 245(4-5), 393 (1995)

[21] T. Ban, S. Ter-Avetisyan, R. Beuc, H. Skenderovic, and G. Pichler, Photoassociation of cesium atoms into the double minimum state, Chem. Phys. Lett. 313(1-2), 110 (1999)

[22] A. Fioretti, D. Comparat, A. Crubellier, O. Dulieu, F. Masnou-Seeuws, and P. Pillet, Formation of cold Cs₂ molecules through photo association, Phys. Rev. Lett. 80(20), 4402 (1998)

[23] H. Lignier, A. Fioretti, R. Horchani, C. Drag, N. Bouloufa, M. Allegrini, O. Dulieu, L. Pruvost, P. Pillet, and D. Comparat, Deeply bound cold caesium molecules formed after 0^-_g resonant coupling, Phys. Chem. Chem. Phys. 13(42), 18910 (2011)

[24] J. Ma, W. Liu, J. Yang, J. Wu, W. Sun, V. S. Ivanov, A. S. Skublov, V. B. Sovkov, X. Dai, and S. Jia, New observation and combined analysis of the Cs₂ 0^-_g, 0⁺_u, and 1_g states at the asymptotes 6S_1/2+ 6P_1/2 and 6S_1/2+ 6P_3/2, J. Chem. Phys. 141(24), 244310 (2014)

[25] A. Fioretti, D. Comparat, C. Drag, C. Amiot, O. Dulieu, F. Masnou-Seeuws, and P. Pillet, Photoassociative spectroscopy of the Cs₂ 0^-_g long-range state, Eur. Phys. J. D 5(3), 389 (1999)

[26] N. Bouloufa, A. Crubellier, and O. Dulieu, Reexamination of the 0_g pure long-range state of Cs₂: Prediction of missing levels in the photoassociation spectrum, Phys. Rev. A 75(5), 052501 (2007)

[27] K. M. Jones, E. Tiesinga, P. D. Lett, and P. S. Julienne, Ultracold photoassociation spectroscopy: Long-range molecules and atomic scattering, Rev. Mod. Phys. 78(2), 483 (2006)

[28] R. Horchani, H. Lignier, N. Bouloufa-Maafa, A. Fioretti, P. Pillet, and D. Comparat, Triplet-singlet conversion by broadband optical pumping, Phys. Rev. A 85(3), 030502 (2012)

[29] M. Raab, G. Höning, W. Demtröder, and C. R. Vidal, High resolution laser spectroscopy of Cs₂ (II): Doppler-free polarization spectroscopy of the C ¹Π _u ←X ¹Σ⁺ _g  system, J. Chem. Phys. 76(9), 4370 (1982)

[30] W. Weickenmeier, U. Diemer, M. Wahl, M. Raab, W. Demtröder, and W. Müller, Accurate ground state potential of Cs2 up to the dissociation limit, J. Chem. Phys. 82(12), 5354 (1985)

[31] R. L. Brooks and J. L. Hunt, Helium hydride emission spectra at 550 and 640 nm, J. Chem. Phys. 89(3), 7077 (1988) http://dx.doi.org/10.1063/1.455337

[32] A. Wakim, P. Zabawa, M. Haruza, and N. P. Bigelow, Luminorefrigeration: vibrational cooling of NaCs, Opt. Express 20(14), 16083 (2012)

[33] T. Schneider, B. Roth, H. Duncker, I. Ernsting, and S. Schiller, All-optical preparation of molecular ions in the rovibrational ground state, Nat. Phys. 6(4), 275 (2010)

[34] P. F. Staanum, K. Höjbjerre, P. S. Skyt, A. K. Hansen, and M. Drewsen, Rotational laser cooling of vibrationally and translationally cold molecular ions, Nat. Phys. 6(4), 271 (2010)

[35] M. Viteau, A. Chotia, M. Allegrini, N. Bouloufa, O. Dulieu, D. Comparat, and P. Pillet, Optical pumping and vibrational cooling of molecules, Science 321(5886), 232 (2008)

[36] D. Sofikitis, S. Weber, A. Fioretti, R. Horchani, M. Allegrini, B. Chatel, D. Comparat, and P. Pillet, Molecular vibrational cooling by optical pumping with shaped femtosecond pulses, New J. Phys. 11(5), 055037 (2009)

[37] A. Kastler, Quelques suggestions concernant la production optique et la détection optique d’une inégalité de population des niveaux de quantifigation spatiale des atomes. Application à l’expérience de Stern et Gerlach et à la résonance magnétique, J. Phys. Radium 11(6), 255 (1950)

[38] J. T. Bahns, W. C. Stwalley, and P. L. Gould, Laser cooling of molecules: A sequential scheme for rotation, translation, and vibration, J. Chem. Phys. 104(24), 9689 (1996)

[39] U. Diemer, R. Duchowicz, M. Ertel, E. Mehdizadeh, W. Demtröder, Doppler-free polarization spectroscopy of the B ¹Π_u state of Cs₂, Chem. Phys. Lett. 164(4), 419 (1989)

[40] D. Sofikitis, R. Horchani, Xiaolin Li, M. Pichler, M. Allegrini, A. Fioretti, D. Comparat, and P. Pillet, Vibrational cooling of cesium molecules using noncoherent broadband light, Phys. Rev. A 80, 051401(R) (2009)

[41] R. Horchani, Femtosecond laser shaping with digital light processing, Opt. Quantum Electron. 47(8), 3023 (2015)

[42] J. Tallant and L. Marcassa, Bull. Am. Phys. Soc. 59, 3004 (2014)

[43] D. Wang, C. Ashbaugh, J. T. Kim, E. E. Eyler, P. L. Gould, and W. C. Stwalley, Rotationally resolved depletion spectroscopy of ultracold KRb molecules, Phys. Rev. A 75(3), 032511 (2007)

[44] K. Aikawa, D. Akamatsu, M. Hayashi, K. Oasa, J. Kobayashi, P. Naidon, T. Kishimoto, M. Ueda, and S. Inouye, Coherent transfer of photoassociated molecules into the rovibrational ground state, Phys. Rev. Lett. 105, 203001 (2010), arXiv: 1008.5034

[45] I. Manai, R. Horchani, H. Lignier, P. Pillet, D. Comparat, A. Fioretti, and M. Allegrini, Phys. Rev. Lett. 109, 183001 (2012) and Viewpoint: Nicholas Bigelow: Deep molecular cooling, Physics 5, 121 (2012)

[46] A. Fioretti, D. Sofikitis, R. Horchani, X. Li, M. Pichler, S. Weber, M. Allegrini, B. Chatel, D. Comparat, and P. Pillet, Cold cesium molecules: from formation to cooling, J. Mod. Opt. 56, 2089 (2009)

[47] J. T. Bahns, W. C. Stwalley, and P. L. Gould, Laser cooling of molecules: A sequential scheme for rotation, translation, and vibration, J. Chem. Phys. 104(24), 9689 (1996)

[48] M. D. Rosa, Laser-cooling molecules, Eur. Phys. J. D 31(2), 395 (2004)

[49] J. Pérez-Ríos, M. Lepers, and O. Dulieu, Theory of long-range ultracold atom-molecule photoassociation, Phys. Rev. Lett. 115(7), 073201 (2015)

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