Simulation design of thin film lithium niobate electro-optic modulator with bimetallic layer electrodes

Abstract

Thin-film lithium niobate electro-optical modulator will become the key device in the future optical communication, which has the advantages of high modulation rate, low half-wave voltage, large bandwidth, and easy integration compared with conventional bulk lithium niobate modulator. However, because the electrode gap of the lithium niobate film modulator is very narrow, when the microwave frequency gets higher, it leads to higher microwave loss, and the electro-optical performance of the modulator will be greatly reduced. Here, we propose a thin film lithium niobate electro-optic modulator with a bimetallic layer electrode structure to achieve microwave loss less than 8 dB/cm in the range of 200 GHz, exhibiting a voltage-length product of 1.1 V·cm and a 3 dB electro-optic bandwidth greater than 160 GHz. High-speed data transmission test has been performed, showing good performance.

References

[1] HaffnerC, ChelladuraiD, FedoryshynY, et al.. Low-loss plasmon-assisted electro-optic modulator. Nature, 2018, 556(7702):483-486 J]

[2] PhareC T, LeeY H D, CardenasJ, et al.. Graphene electro-optic modulator with 30 GHz bandwidth. Nature photonics, 2015, 9(8):511-514 J]

[3] HanJ H, BoeufF, FujikataJ, et al.. Efficient low-loss InGaAsP/Si hybrid MOS optical modulator. Nature photonics, 2017, 11(8):486-490 J]

[4] LeeM, KatzH E, ErbenC, et al.. Broadband modulation of light by using an electro-optic polymer. Science, 2002, 298(5597):1401-1403 J]

[5] AlloattiL, PalmerR, DieboldS, et al.. 100 GHz silicon-organic hybrid modulator. Light: science & applications, 2014, 3(5):e173 J]

[6] WangC, ZhangM, ChenX, et al.. Integrated lithium niobate electro-optic modulators operating at CMOS-compatible voltages. Nature, 2018, 562: 101-104 J]

[7] HeM, XuM, RenY, et al.. High-performance hybrid silicon and lithium niobate Mach-Zehnder modulators for 100 Gbits⁻¹ and beyond. Nature photonics, 2019, 13: 359-364 J]

[8] AhmedA N R, ShiS, MercanteA, et al.. High-efficiency lithium niobate modulator for K band operation. APL photonics, 2020, 5: 091302 J]

[9] PrashantaK, ChristianR, KevinL, et al.. Breaking voltage-bandwidth limits in integrated lithium niobate modulators using micro-structured electrodes. Optica, 2021, 8: 357-363 J]

[10] GhioneG. Semiconductor devices for high-speed optoelectronics, 2009, Oxford, Oxford University M]

[11] AokiK, KondouJ, MitomiO, et al.. Velocity-matching conditions for ultrahigh-speed optical LiNbO₃ modulators with traveling-wave electrode. Japanese journal of applied physics, 2006, 45: 8696-8698 J]

[12] GuJ H, WuB Y. Analysis on the microwave attenuation coefficient of traveling-wave electrodes with complicated cross-sections in Ti: LiNbO₃ optical modulators. Acta electronica sinica, 1998, 26(6):58-61[J]

[13] RaoA, FathpourS. Compact lithium niobate electrooptic modulators. IEEE journal of selected topics in quantum electronics, 2018, 24(4):1-14 J]

[14] FrankelY, GuptaS, ValdmanisJ A, et al.. Terahertz attenuation and dispersion characteristics of coplanar transmission lines. IEEE transactions on microwave theory and techniques, 1991, 39(6):910-916 J]

[15] YuL Y, ShangJ M, LuoK W, et al.. Design of high-speed mid-infrared electro-optic modulator based on thin film lithium niobate. IEEE photonics journal, 2022, 14(2):1-6[J]

[16] AndrewJ M, YaoP, ShiS Y, et al.. 110 GHz CMOS compatible thin film LiNbO₃ modulator on silicon. Optics express, 2016, 24: 15590-15595 J]

[17] HanH, YangF, LiuC, et al.. High-performance electro-optical Mach-Zehnder modulators in a silicon nitride-lithium niobate thin-film hybrid platform. Photonics, 2022, 9: 500 J]

[18] SunS, HeM, XuM, et al.. Hybrid silicon and lithium niobate modulator. IEEE journal of selected topics in quantum electronics, 2021, 27(3):1-12 J]

[19] PanB C, HuJ Y, HuangY S, et al.. Demonstration of high-speed thin-film lithium-niobate-on-insulator optical modulators at the 2-µm wavelength. Optics express, 2021, 29: 17710-17717 J]

[20] CaiJ, GuoC, LuC, et al.. Design optimization of silicon and lithium niobate hybrid integrated traveling-wave Mach-Zehnder modulator. IEEE photonics journal, 2021, 13(4):1-6 J]

[21] ZhuD, ShaoL B, YuM, et al.. Integrated photonics on thin-film lithium niobate. Advances in optics and photonics, 2021, 13: 242-352 J]

[22] WeigelP O, ValdezF, ZhaoJ, et al.. Design of high-bandwidth, low-voltage and low-loss hybrid lithium niobate electro-optic modulators. Journal of physics: photonics, 2021, 3(1): 012001[J]