-
全固态被动调Q激光器的非线性动力学行为是影响其输出特性的关键因素. 本文通过数值模拟研究了泵浦调制下全固态被动调Q Nd:YAG/Cr:YAG激光器的非线性动力学行为, 讨论了关键调制参量对调Q激光非线性动力学及其输出特性的影响. 仿真结果表明, 在特定的调制频率、调制幅度以及未调制泵浦速率下, 调Q激光可以表现出单周期态、倍周期态、多周期态以及混沌态. 通过分析调Q激光脉冲峰值随调制频率、调制幅度以及未调制泵浦速率变化的分岔图, 发现脉冲峰值主要经倍周期和准周期演化路径进入混沌. 此外, 脉冲频率(即相邻脉冲时间间隔的倒数)进入混沌的演化路径与脉冲峰值的演化路径一致, 但脉冲频率强度变化趋势与脉冲峰值强度变化趋势相反. 研究结果理论上揭示了泵浦调制关键参量对激光器的非线性动力学行为及其输出特性具有显著影响, 并为进一步实验深入探究其演化机制提供了重要的指导.
-
关键词:
- 泵浦调制 /
- 全固态被动调Q激光器 /
- Nd:YAG/Cr:YAG /
- 非线性动力学
All-solid-state passively Q-switched lasers can exhibit nonlinear behaviors such as period-doubling, injection locking, and chaos under specific conditions, offering new applications in fields like secure communication and random number generation. As a result, the nonlinear dynamics of laser systems are becoming increasingly important. Pump modulation is a typical method of controlling the nonlinear dynamical states of solid-state lasers. In this work, the nonlinear dynamical characteristics of an all-solid-state passively Q-switched Nd:YAG/Cr:YAG laser under pump modulation are investigated by solving a four-level rate equation system using the Runge-Kutta method. The results demonstrate that by adjusting key parameters including modulation frequency, modulation amplitude, and unmodulated pump rate, the laser system can exhibit rich dynamical states, including period-one, period-two, multi-period, and chaotic pulsation. By analyzing the bifurcation diagram, the evolution pattern of output laser pulse characteristics with parameter changes is revealed. The system mainly enters chaos through period-doubling and quasi-periodic routes, while exhibiting a unique phenomenon where the pulse peak and pulse frequency follow synchronized evolutionary paths but with opposite trends in intensity variation, indicating dynamic coupling effects between frequency and intensity domains. By constructing the nonlinear dynamical distributions within a three-dimensional pump modulation parameter space, the combined effects of modulation frequency, modulation amplitude, and unmodulated pump rate on the evolution of the laser's nonlinear dynamics are systematically investigated in this work. The results show that at lower unmodulated pump rates, the system cannot be driven into nonlinear states even when the modulation amplitude and frequency are relatively large. In contrast, under higher unmodulated pump rates, the appropriate tuning of modulation amplitude and frequency enables the system to transition from periodic states to chaotic behavior. This work not only elucidates the modulation mechanisms of pump parameters on the nonlinear dynamics of lasers, but also provides theoretical guidance for optimizing laser output performance and designing high-performance chaotic lasers, which is of great significance in promoting the applications of Q-switched lasers in precision measurement and secure communication fields.-
Keywords:
- pump modulation /
- all-solid-state passively Q-switched laser /
- Nd:YAG/Cr:YAG /
- nonlinear dynamics
-
图 2 (a) 泵浦速率随时间的变化; (b) 光子数密度随时间的变化; (c) 增益介质反转粒子数密度随时间的变化; (d) 可饱和吸收体粒子数密度随时间的变化
Fig. 2. (a) Temporal evolution of the pump rate; (b) temporal evolution of photon number density; (c) temporal evolution of gain medium inversion population density; (d) temporal evolution of saturable absorber population density.
图 3 当未调制泵浦速率和调制幅度分别为1000 s–1和50%时, 不同调制频率下调Q激光脉冲序列、三维相图、轨迹图和分岔图 (a1)—(c1), (a2)—(c2), (a3)—(c3)分别为在调制频率为200, 220, 270 kHz下调Q激光脉冲序列、三维相图和轨迹图; (d1)和(d2)分别为调Q激光脉冲峰值和脉冲频率随调制频率变化的分岔图
Fig. 3. When the unmodulated pump rate and modulation amplitude are 1000 s–1 and 50%, respectively, Q-switched laser pulse trains, 3D phase portraits, trajectory diagrams and bifurcation diagrams at different modulation frequencies. Panel (a1)–(c1), (a2)–(c2) and (a3)–(c3) show Q-switched laser pulse trains, 3D phase portraits and trajectory diagrams at modulation frequencies of 200, 220 and 270 kHz, respectively. Panel (d1) and (d2) present bifurcation diagrams of Q-switched laser pulse peak and pulse frequency versus modulation frequency.
图 4 当未调制泵浦速率和调制频率分别为1000 s–1和500 kHz时, 不同调制幅度下调Q激光脉冲序列、三维相图、轨迹图和分岔图 (a1)—(c1), (a2)—(c2), (a3)—(c3), (a4)—(c4)分别为调制幅度为20%, 40%, 48%, 55%下调Q激光脉冲序列、相图和轨迹图; (d1)和(d2)分别为调Q激光脉冲峰值和脉冲频率随调制幅度变化的分岔图
Fig. 4. When the unmodulated pump rate and modulation frequency are 1000 s–1 and 500 kHz, respectively, Q-switched laser pulse trains, 3D phase portraits, trajectory diagrams and bifurcation diagrams under different modulation amplitude. Panel (a1)–(c1), (a2)–(c2), (a3)–(c3) and (a4)–(c4) show Q-switched laser pulse trains, phase portraits and trajectory diagrams at modulation amplitude of 20%, 40%, 48% and 55%, respectively. Panel (d1) and (d2) present bifurcation diagrams of Q-switched laser pulse peak and pulse frequency versus modulation amplitude.
图 5 当调制幅度和调制频率分别为50%和500 kHz时, 不同未调制泵浦速率下调Q激光脉冲序列、三维相图、轨迹图和分岔图 (a1)—(c1), (a2)—(c2), (a3)—(c3)分别为未调制泵浦速率为1200, 1300, 1400 s–1下调Q激光脉冲序列、三维相图和轨迹图; (d1)和(d2)分别为调Q激光脉冲峰值和脉冲频率随未调制泵浦速率变化的分岔图
Fig. 5. When the modulation amplitude and modulation frequency are 50% and 500 kHz, respectively, Q-switched laser pulse trains, 3D phase portraits, trajectory diagrams and bifurcation diagrams under different unmodulated pump rates. Panel (a1)–(c1), (a2)–(c2) and (a3)–(c3) show Q-switched laser pulse trains, 3D phase portraits and trajectory diagrams at unmodulated pump rates of 1200, 1300 and 1400 s–1, respectively. Panel (d1) and (d2) present bifurcation diagrams of Q-switched laser pulse peak and pulse frequency versus unmodulated pump rate.
图 6 在调制频率fm、调制幅度Am、未调制泵浦速率P0构成的参数空间内脉冲峰值的非线性动力学分布 (a) fm = 500 kHz时, P0与Am构成参数空间内的非线性动力学分布; (b) Am = 50%时, fm与P0构成参数空间内的非线性动力学分布; (c) P0 = 1000 s–1时, Am与fm构成参数空间内的非线性动力学分布
Fig. 6. Dynamic distributions of pulse peak in the parameter space of the modulation frequency fm, modulation amplitude Am, and unmodulated pump rate P0: (a) P0 and Am under fm = 500 kHz; (b) fmand P0 under Am = 50%; (c) Am and fm under P0= 1000 s–1.
-
[1] Shen J P, Chen Y, Chen L, Xing F Y, Zhang F B, Xia R Z, Zuo H Y, Xiong F, Jiang R R 2025 Chin. Phys. Lett. 42 044202
Google Scholar
[2] 刘杨, 刘兆军, 丛振华, 徐晓东, 徐军, 门少杰, 夏金宝, 张飒飒 2015 64 174203
Google Scholar
Liu Y, Liu Z J, Cong Z H, Xu X D, Xu J, Men S J, Xia J B, Zhang S S 2015 Acta Phys. Sin 64 174203
Google Scholar
[3] Pavel N, Dascalu T, Salamu G, Dinca M, Boicea N, Birtas A 2015 Opt. Express 23 33028
Google Scholar
[4] Huang C X, Zhou L J, Zhong L X, Liang J D, Ma L, Chen G D, Li Z J, Lu T, Jin C J 2025 Opt. Laser Technol. 184 112485
Google Scholar
[5] Dascalu T, Croitoru G, Grigore O, Pavel N 2016 Photonics Res. 4 267
Google Scholar
[6] Han S, Du Q H, Geng L, Liu X L, Zhao H Y, Liu Y Q, Zhang S B, Yang X Q 2025 Opt. Laser Technol. 181 111642
Google Scholar
[7] Dun Y Y, Li P, Chen X H, Ma B M 2016 Chin. Phys. Lett. 33 024201
Google Scholar
[8] He Y, Ma Y F, Li J, Li X D, Yan R P, Gao J, Yu X, Sun R, Pan Y B 2016 Opt. Laser Technol. 81 46
[9] Uchida A, Amano K, Inoue M, Hirano K, Naito S, Someya H, Oowada I, Kurashige T, Shiki M, Yoshimori S, Yoshimura K, Davis P 2008 Nat. Photonics 2 728
Google Scholar
[10] Sciamanna M, Shore K A 2015 Nat. Photonics 9 151
Google Scholar
[11] Argyris A, Syvridis D, Larger L, Annovazzi-Lodi V, Colet P, Fischer L, Garcia-Ojalvo J, Mirasso C R, Pesquera L, Shore K A 2005 Nature 438 343
Google Scholar
[12] Lin F Y, Liu J M 2004 IEEE J. Sel. Top. Quantum Electron. 10 991
Google Scholar
[13] Tang D Y, Ng S P, Qin L J, Meng X L 2003 Opt. Lett. 28 325
Google Scholar
[14] Ng S P, Tang D Y, Qin L J, Meng X L, Xiong Z L 2006 Int. J. Bifurcation Chaos 16 2689
Google Scholar
[15] Kovalsky M, Hnilo A 2010 Opt. Lett. 35 3498
Google Scholar
[16] Tsai S Y, Chiu C P, Chang K C, Wei M D 2016 Opt. Lett. 41 1054
Google Scholar
[17] 高子叶, 夏光琼, 邓涛, 林晓东, 唐曦, 樊利, 吴正茂 2021 光子学报 50 0314001
Gao Z Y, Xia G Q, Deng T, Lin X D, Tang X, Fan L, Wu Z M 2021 Acta Photonica Sin. 50 0314001
[18] 高子叶, 夏光琼, 邓涛, 林晓东, 唐曦, 樊利, 吴正茂 2023 西南大学学报(自然科学版) 45 195
Gao Z Y, Xia G Q, Deng T, Lin X D, Tang X, Fan L, Wu Z M 2023 J. Southwest Univ. (Nat. Sci. Ed.) 45 195
[19] Hurtado A, Quirce A, Valle A, Pesquera L, Adams M J 2010 Opt. Express 18 9423
Google Scholar
[20] Li X F, Pan W, Luo B, Ma D 2006 Chaos, Solitons Fractals 30 1004
Google Scholar
[21] Wei M D, Hsu C C, Huang H H, Wu H H 2010 Opt. Express 18 19977
Google Scholar
[22] Hong K G, Wei M D 2013 J. Opt. 15 085201
Google Scholar
[23] Villafana-Rauda E, Chiu R, Mora-Gonzalez M, Casillas-Rodriguez F, Medel-Ruiz C L, Sevilla-Escoboza R 2019 Results Phys. 12 908
Google Scholar
下载:
计量
- 文章访问数: 339
- PDF下载量: 5
- 被引次数: 0
