用于波面倾斜产生高能量太赫兹波的接触光栅设计

基于非共线相位匹配的波面倾斜技术是目前采用飞秒激光产生超快太赫兹波最有效的手段，使用接触式光栅直接产生抽运飞秒脉冲的波面倾斜能够克服成像系统引入的畸变从而进一步提高该技术的效率。提出并利用简化的模态法设计了制备于铌酸锂晶体中用于波面倾斜技术产生高能量太赫兹波的内嵌式接触光栅。将Littrow角入射条件下的光栅衍射理论简化为光栅内双模式的干涉过程，极大地简化了光栅的参数设计。确定了满足波面倾斜条件的光栅常数，系统研究了衍射效率与光栅占空比和刻槽深度的关系，通过内嵌式光栅结构降低反射损耗,理论上能达到90%以上的-1级衍射效率，给出了合适的光栅加工参数。该系统设计方法对基于其他太赫兹波产生晶体的接触光栅设计具有参考意义。

Abstract

Titled pulse front pumping (TPFP) based on non-collinear phase matching is the most efficient technique to generate ultrafast terahertz (THz) wave by femtosecond laser sources, and the use of a contact grating that can avoid aberrations caused by the imaging system has the potential of further improving the generation efficiency. An embedded contact grating fabricated inside the lithium niobate crystal is proposed for the TPFP scheme for the generation of high-energy THz radiation and designed by the simplified modal method. The grating diffraction under the Littrow mounting is simplified to a two-mode interference process, which greatly simplifies the grating design. The grating period is determined and the dependence of the diffraction efficiency on the fill factor and the groove depth of the grating is systematically explored. By reducing the reflection at the grating-crystal interface the embedded grating can achieve a diffraction efficiency larger than 90% for the -1 diffraction order and the grating parameters are given. This systematic design procedure is applicable to the design of contact gratings based on other THz generation crystals.

参考文献

[1] B Ferguson, X C Zhang. Materials for terahertz science and technology[J]. Nat Mater, 2002, 1(1): 26-33.

[2] M Tonouchi. Cutting-edge terahertz technology[J]. Nat Photon, 2007, 1(2): 97-105.

[3] Y C Shen, T Lo, P F Taday, et al.. Detection and identification of explosives using terahertz pulsed spectroscopic imaging[J]. Appl Phys Lett, 2005, 86(24): 241116.

[4] 冯瑞姝，李微微，周庆莉，等. RDX及其混合炸药的太赫兹光谱的研究[J]. 光学学报, 2009, 29(s1): 262-265.

Feng Ruishu, Li Weiwei, Zhou Qingli, et al.. Terahertz spectroscopic investigations of explosives and the related compounds[J]. Acta Optica Sinica, 2009, 29(s1): 262-265.

[5] 张存林，牧凯军. 太赫兹波谱与成像[J]. 激光与光电子学进展, 2010, 47(2): 023001.

Zhang Cunlin, Mu Kaijun. Terahertz spectroscopy and imaging[J]. Laser & Optoelectronics Progress, 2010, 47(2): 023001.

[6] S M Kim, W Baughman, D S Wilbert, et al.. High sensitivity and high selectivity terahertz biomedical imaging[J]. Chin Opt Lett, 2011, 9(11): 110009.

[7] Y Zhu, S Zhuang. Terahertz electromagnetic waves emitted from semiconductor investigated using terahertz time domain spectroscopy[J]. Chin Opt Lett, 2011, 9(11): 110007.

[8] 董杰，栗岩锋，束李，等. 高调制度光致相变特性氧化钒薄膜太赫兹时域频谱研究[J]. 中国激光，2014，41(1): 0111001.

Dong Jie, Li Yanfeng, Shu Li, et al.. Study of photo-induced phase transition of VO2 films with high modulation by time-domain spectroscopy[J]. Chinese J Lasers, 2014, 41(1): 0111001.

[9] M C Hoffmann, J A Fülp. Intense ultrashort terahertz pulses: generation and applications[J]. J Phys D: Appl Phys, 2011, 44(8): 083001.

[10] J Li, L Chai, J Shi, et al.. Generation of 0.3 mW high-power broadband terahertz pulses from GaP crystal pumped by negatively chirped femtosecond laser pulses[J]. Laser Phys Lett, 2013, 10(12): 125404.

[11] W Wang, Z Sheng, Y Li, et al.. Studies on the mechanisms of powerful terahertz radiations from laser plasmas[J]. Chin Opt Lett, 2011, 9(11): 110002.

[12] L Xu, X C Zhang, D H Auston. Terahertz beam generation by femtosecond optical pulses in electro-optic materials[J]. Appl Phys Lett, 1992, 61(15): 1784-1786.

[13] A Nahata, A S Weling, T F Heinz. A wideband coherent terahertz spectroscopy system using optical rectification and electro-optic sampling[J]. Appl Phys Lett, 1996, 69(16): 2321-2323.

[14] J Hebling, G Almási, I Z Kozma, et al.. Velocity matching by pulse front tilting for large-area THz-pulse generation[J]. Opt Express, 2002, 10(21): 1161-1166.

[15] J A Fülp, L Pálfalvi, S Klingebiel, et al.. Generation of sub-mJ terahertz pulses by optical rectification[J]. Opt Lett, 2012, 37(4): 557-559.

[16] S W Huang, E Granados, W R Huang, et al.. High conversion efficiency, high energy terahertz pulses by optical rectification in cryogenically cooled lithium niobate[J]. Opt Lett, 2013, 38(5): 796-798.

[17] J Hebling, K L Yeh, M C Hoffmann, et al.. Generation of high-power terahertz pulses by tilted-pulse-front excitation and their application possibilities[J]. J Opt Soc Am B, 2008, 25(7): B6-B19.

[18] H Hirori, K Tanaka. Nonlinear optical phenomena induced by intense single-cycle terahertz pulses[J]. IEEE J Sel Top Quantum Electron, 2013, 19(1): 8401110.

[19] J A Fülp, L Pálfalvi, G Almási, et al.. Design of high-energy terahertz sources based on optical rectification[J]. Opt Express, 2010, 18(12): 12311-12327.

[20] L Pálfalvi, J A Fülp, G Almási, et al.. Novel setups for extremely high power single-cycle terahertz pulse generation by optical rectification[J]. Appl Phys Lett, 2008, 92(17): 171107.

[21] K Nagashima, A Kosuge. Design of rectangular transmission gratings fabricated in LiNbO3 for high-power terahertz-wave generation [J]. Jap J Appl Phys, 2010, 49(12): 122504.

[22] Z Ollmann, J Hebling, G Almási. Design of a contact grating setup for mJ-energy THz pulse generation by optical rectification[J]. Appl Phys B, 2012, 108(4): 821-826.

[23] A V Tishchenko. Phenomenological representation of deep and high contrast lamellar gratings by means of the modal method[J]. Opt Quantum Electron, 2005, 37(1-3): 309-330.

[24] T Clausnitzer, T Kmpfe, E B Kley, et al.. An intelligible explanation of highly-efficient diffraction in deep dielectric rectangular transmission gratings[J] Opt Express, 2005, 13(26): 10448-10456.

[25] T Clausnitzer, T Kmpfe, E B Kley, et al.. Highly-dispersive dielectric transmission gratings with 100% diffraction efficiency[J]. Opt Express, 2008, 16(8): 5577-5584.

[26] 郑将军. 光栅简化模式方法及应用[D]. 上海：中国科学院上海光学精密机械研究所, 2009.

Zheng Jiangjun. Simplified Modal Method of Gratings and Applications[D]. Shanghai: Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, 2009.

[27] J Zheng, C Zhou,J Feng, et al... Polarizing beam splitter of deep-etched triangular-groove fused-silica gratings[J]. Opt Lett, 2008, 33(14): 1554-1556.

[28] J Hebling. Derivation of the pulse front tilt caused by angular dispersion[J]. Opt Quantum Electron, 1996, 28(12): 1759-1763.

[29] M G Moharam, D A Pommet, E B Grann, et al.. Stable implementation of the rigorous coupled-wave analysis for surface-relief gratings: enhanced transmittance matrix approach[J]. J Opt Soc Am A, 1995, 12(5): 1077-1086.

[30] I C Botten, M S Craig, R C McPhedran, et al.. The dielectric lamellar diffraction grating[J].Optica Acta,1981,28(3): 413-428.

[31] M Nakamura, S Higuchi, S Takekawa, et al.. Optical damage resistance and refractive indices in near-stoichiometric MgO-doped LiNbO3[J]. Jpn J Appl Phys, 2002, 41(1A/B): L49-L51.

[32] L Pálfalvi, J Hebling, J Kuhl, et al.. Temperature dependence of the absorption and refraction of Mg-doped congruent and stoichiometric LiNbO3 in the THz range[J]. J Appl Phys, 2005, 97(12): 123505.

[33] Z Ren, P J Heard, J M Marshall, et al.. Etching characteristics of LiNbO3 in reactive ion etching and inductively coupled plasma[J]. J Appl Phys, 103(3): 034109.

[34] A Suzuki, T Iwamoto, A Enokihara, et al.. Fabrication of Bragg gratings with deep grooves in LiNbO3 ridge optical waveguide[J]. Microelectron Eng, 2008, 85(5-6): 1417-1420.

[35] Z Ollmann, J A Fülp, J Hebling, et al.. Design of a high-energy terahertz pulse source based on ZnTe contact grating[J]. Opt Commun, 2014, 315: 159-163.

梁晓晶, 栗岩锋, 胡晓堃, 徐帅帅, 柴路, 王清月. 用于波面倾斜产生高能量太赫兹波的接触光栅设计[J]. 中国激光, 2014, 41(8): 0811001. Liang Xiaojing, Li Yanfeng, Hu Xiaokun, Xu Shuaishuai, Chai Lu, Wang Qingyue. Design of Contact Grating for High Energy Terahertz Wave Generation by Tilted Pulse Front Pumping[J]. Chinese Journal of Lasers, 2014, 41(8): 0811001.

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