Direct generation of ultrashort pulse sequence by optical parametric process
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摘要: 论证了单晶体光参量放大（OPA）过程在特定边界条件下满足频域宇称-时间（PT）反对称性。归一化的数值求解结果显示，OPA系统PT对称阈值点附近呈现增益跃变性质。对于存在位相失配的OPA，通过实时调控泵浦光强，即可控制系统PT对称性，论文基于相位失配OPA中可超快调控PT对称性的特性构建了超快光开关，一方面光开关与周期性幅度调制的泵浦光联合使用，可直接将连续激光转换为超短脉冲序列输出；另一方面，构建的光开关也可用于脉冲激光再压缩，有望用于中红外波等长波段超短种子源。论文提出的基于超快光开关直接产生超短脉冲序列的方案，由于不需要光学谐振腔，易于实现大于10 GHz的超高重复频率。Abstract: This paper demonstrates that the single crystal optical parametric amplification process (OPA) satisfies spectral parity-time (PT) anti-symmetry under specific boundary conditions, and the PT symmetry threshold point exhibits a gain jump property. For an OPA with phase mismatch, the PT symmetry of the system can be controlled by instantaneous adjustment of the pump intensity. Based on this property, this paper constructs an ultrafast optical switch, which can combine with amplitude modulated pump to directly convert continuous laser into an ultrashort output pulse sequence. On the other hand, the optical switch can be used for further pulse compression and is promising to be used as an ultrashort mid-infrared seed source. The proposed scheme is easy to directly generate ultrashort pulse sequence with repetition rate higher than 10 GHz because the optical resonant cavity is not required.
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图 1 本征值和本征模式传输特性在不同∆k和Г下的演化
Figure 1. The engenvalues and transmission characteristics of engenmodes versus ∆k and Г
图 2 ∆k = 2时，信号光（蓝色）和闲频光（红色）的强度随z和Г的演化
Figure 2. Intensity of signal (blue) and idler (red) versus z and Г for ∆k = 2
图 3 正弦调制泵浦光驱动下，经过z=10的归一化长度传播后信号光的输出结果
Figure 3. Output signal driven by sinusoidal modulated pump for z=10
图 4 信号时域波形、脉宽、对比度随归一化长度z的演化
Figure 4. Temporal waveforms, pulse duration, and output contrast of signal versus z
图 5 直接产生脉冲序列的计算结果−5
Figure 5. Numerical simulation results for directly generated pulse sequence
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[1] Udem T, Holzwarth R, Hänsch T W. Optical frequency metrology[J]. Nature, 2002, 416(6877): 233-237. doi: 10.1038/416233a [2] Hasegawa A, Tappert F. Transmission of stationary nonlinear optical pulses in dispersive dielectric fibers. I. Anomalous dispersion[J]. Appl Phys Lett, 1973, 23(3): 142-144. doi: 10.1063/1.1654836 [3] Peyman G A. Method for modifying corneal curvature: 4840175[P]. 1989-06-20. [4] McCracken R A, Charsley J M, Reid D T. A decade of astrocombs: recent advances in frequency combs for astronomy [Invited][J]. Opt Express, 2017, 25(13): 15058-15078. doi: 10.1364/OE.25.015058 [5] IMT Vision—Framework and overall objectives of the future development of IMT for 2020 and beyond[R]. ITU-R M. 2083-0, 2015. [6] Bender C M, Boettcher S. Real spectra in non-Hermitian Hamiltonians having PT symmetry[J]. Phys Rev Lett, 1998, 80(24): 5243-5246. doi: 10.1103/PhysRevLett.80.5243 [7] Guo A, Salamo G J, Duchesne D, et al. Observation of PT-symmetry breaking in complex optical potentials[J]. Phys Rev Lett, 2009, 103: 093902. doi: 10.1103/PhysRevLett.103.093902 [8] Rüter C E, Makris K G, El-Ganainy R, et al. Observation of parity–time symmetry in optics[J]. Nat Phys, 2010, 6(3): 192-195. doi: 10.1038/nphys1515 [9] Wiersig J. Enhancing the sensitivity of frequency and energy splitting detection by using exceptional points: application to microcavity sensors for single-particle detection[J]. Phys Rev Lett, 2014, 112: 203901. doi: 10.1103/PhysRevLett.112.203901 [10] Lai Y H, Lu Y K, Suh M G, et al. Observation of the exceptional-point-enhanced Sagnac effect[J]. Nature, 2019, 576(7785): 65-69. doi: 10.1038/s41586-019-1777-z [11] Ramezani H, Kottos T, El-Ganainy R, et al. Unidirectional nonlinear PT-symmetric optical structures[J]. Phys Rev A, 2010, 82: 043803. doi: 10.1103/PhysRevA.82.043803 [12] Antonosyan D A, Solntsev A S, Sukhorukov A A. Parity-time anti-symmetric parametric amplifier[J]. Opt Lett, 2015, 40(20): 4575-4578. doi: 10.1364/OL.40.004575 [13] Ma Jingui, Wang Jing, Yuan Peng, et al. Quasi-parametric amplification of chirped pulses based on a Sm3+-doped yttrium calcium oxyborate crystal[J]. Optica, 2015, 2(11): 1006-1009. doi: 10.1364/OPTICA.2.001006 [14] Zhong Q, Ahmed A, Dadap J I, et al. Parametric amplification in quasi-PT symmetric coupled waveguide structures[J]. New J Phys, 2016, 18: 125006. doi: 10.1088/1367-2630/18/12/125006 [15] Flemens N, Moses J. Hermitian nonlinear wave mixing controlled by a PT-symmetric phase transition[J]. Phys Rev Lett, 2022, 129: 153901. doi: 10.1103/PhysRevLett.129.153901 [16] Witte S, Eikema K S E. Ultrafast optical parametric chirped-pulse amplification[J]. IEEE Journal of Selected Topics in Quantum Electronics, 2012, 18(1): 296-307. doi: 10.1109/JSTQE.2011.2118370 [17] Özdemir Ş K, Rotter S, Nori F, et al. Parity–time symmetry and exceptional points in photonics[J]. Nat Mater, 2019, 18(8): 783-798. doi: 10.1038/s41563-019-0304-9 [18] Mücke O D, Sidorov D, Dombi P, et al. Scalable Yb-MOPA-driven carrier-envelope phase-stable few-cycle parametric amplifier at 1.5 μm[J]. Opt Lett, 2009, 34(2): 118-120. doi: 10.1364/OL.34.000118 [19] Ganeev R A, Kulagin I A, Ryasnyansky A I, et al. Characterization of nonlinear optical parameters of KDP, LiNbO3 and BBO crystals[J]. Opt Commun, 2004, 229(1/6): 403-412. [20] Gayer O, Sacks Z, Galun E, et al. Temperature and wavelength dependent refractive index equations for MgO-doped congruent and stoichiometric LiNbO3[J]. Appl Phys B, 2008, 91(2): 343-348. doi: 10.1007/s00340-008-2998-2 -
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