Passively Q-switched solid-state lasers offer several advantages, including a compact structure, stable output performance, and high monochromaticity. Consequently, they are extensively employed in a wide range of applications, including industrial manufacturing, scientific research, biomedical fields, and national defense technologies. However, the use of two-dimensional materials, such as graphene, as saturable absorbers in solid-state lasers to achieve Q-switched output has been shown to exhibit decreased stability.In this study, the nonlinear optical characteristics of graphene are incorporated into the simulation model, and the Q-switched rate equations based on a four-level energy system are numerically solved using the fourth-order Runge-Kutta method. This approach successfully generates a stable Q-switched pulse sequence. Furthermore, this paper examines how variations in key system parameters, such as pump rate and intracavity losses, influence pulse width in passively Q-switched lasers. It also explores the dynamic behavior of crucial parameters, including photon number density, inversion particle number, and ground state particle number, thereby revealing insights into the laser's operational dynamics.

Danqing Long, Tianlong Bai. Numerical Simulation of Passive Q-switched Solid-state Laser Based on Graphene. International Journal of Frontiers in Engineering Technology (2024), Vol. 6, Issue 6: 8-17. https://doi.org/10.25236/IJFET.2024.060602.

[1] Meier, M., Romano, V., & Feurer, T. (2007). Material processing with pulsed radially and azimuthally polarized laser radiation. Applied Physics A, 86, 329-334.

[2] Vanwiggeren, G. D., & Roy, R. (1998). Communication with chaotic lasers. Science, 279(5354), 1198-1200.

[3] Corkum, P. B., Brunel, F., Sherman, N. K., & Srinivasan-Rao, T. (1988). Thermal response of metals to ultrashort-pulse laser excitation. Physical review letters, 61(25), 2886.

[4] Wei C.J, Yan R.P, Li X.D, Meng X.X, & Liu X.Y (2021). Research progress on sub nanosecond lasers for 3D imaging lidar applications. Optical Precision Engineering (06), 1270-1280

[5] Salem, A., El Harras, M., Ramadan, A., Gamil, H., Abdul Rahman, A., & El-Said, K. (2010). Use of the Q-switched Nd: YAG laser for the treatment of pigmentary disorders in Egyptians. Journal of Cosmetic and Laser Therapy, 12(2), 92-100.

[6] Flegel, L., Kherani, F., & Richer, V. (2022). Review of eye injuries associated with dermatologic laser treatment. Dermatologic Surgery, 48(5), 545-550.

[7] Wagner, A., Lütke, M., Wetzig, A., & Eng, L. M. (2013). Laser remote-fusion cutting with solid-state lasers. Journal of Laser Applications, 25(5).

[8] Song, Y. W., Jang, S. Y., Han, W. S., & Bae, M. K. (2010). Graphene mode-lockers for fiber lasers functioned with evanescent field interaction. Applied Physics Letters, 96(5).

[9] Popa, D., Sun, Z., Hasan, T., Torrisi, F., Wang, F., & Ferrari, A. C. (2011). Graphene Q-switched, tunable fiber laser. Applied Physics Letters, 98(7).

[10] Wu G, Zhang Z, Wang T, Ji L.L, Cui Y, Gao Y.G&Sui Z (2024). LD end pumped Tm: SrF2 electro-optic Q-switched laser. Intense Laser and Particle Beam (06), 52-57

[11] Guo, L., Yang, Y., Wang, R., Zhang, B., Li, T., Zhao, S., ... & Yang, K. (2021). Experimental and theoretical study of an actively Q-switched TM: YLF laser with an acousto-optic modulator. Molecules, 26(23), 7324.

[12] Gao, L., Ding, Y., Zhai, X., Min, H., Liu, G., Lan, R., & Shen, Y. (2024). Passively Q-switched 2 μm laser based on graphene/BN heterostructure as saturable absorber. Optics & Laser Technology, 168, 109852.

[13] Zhao, J., Yang, X., Liu, Y., Jin, L., Yu, R., Zhou, X., & Cheng, P. (2024). Passively Q-switched 2.3 μm Tm: YVO 4 laser using a Cr: ZnS saturable absorber. Optics Letters, 49(4), 862-865.

[14] Dong, J., Shirakawa, A., & Ueda, K. I. (2005). Numerical simulation of a diode-laser-pumped self-Q-switched Cr, Yb: YAG microchip laser. Optical review, 12, 170-178.

[15] Yu-Ye, W., De-Gang, X., Jing-Ping, X., Zhuo, W., Peng, W., & Jian-Quan, Y. (2008). Numerical modelling of QCW-pumped passively Q-switched Nd: YAG lasers with Cr4+: YAG as saturable absorber. Chinese Physics Letters, 25(8), 2880.

[16] Aubourg, A., Didierjean, J., Aubry, N., Balembois, F., & Georges, P. (2013). Passively Q-switched diode-pumped Er: YAG solid-state laser. Optics letters, 38(6), 938.

[17] Lin, Y. Y., Lee, P., Xu, J. L., Wu, C. L., Chou, C. M., Tu, C. Y., ... & Lee, C. K. (2016). High-pulse-energy topological insulator Bi 2 Te 3-based passive Q-switched solid-state laser. IEEE Photonics Journal, 8(4), 1-10.

[18] Li, L., Cui, W., Yang, X., Zhou, L., Yang, Y., Xie, W., ... & Han, J. (2020). A high-beam-quality passively Q-switched 2 μm solid-state laser with a WSe2 saturable absorber. Optics & Laser Technology, 125, 105960.

[19] Du, Y., Yao, B., Duan, X., Cui, Z., Ding, Y., Ju, Y., & Shen, Z. (2013). Cr: ZnS saturable absorber passively Q-switched Tm, Ho: GdVO 4 laser. Optics Express, 21(22), 26506-26512.

[20] Zayhowski, J. J., & Kelley, P. L. (1991). Optimization of Q-switched lasers. IEEE journal of quantum electronics, 27(9), 2220-2225.

[21] Koechner, W. (2013). Solid-state laser engineering (Vol. 1). Springer.

[22] Tang, D. Y., Ng, S. P., Qin, L. J., & Meng, X. L. (2003). Deterministic chaos in a diode-pumped Nd: YAG laser passively Q switched by a Cr 4+: YAG crystal. Optics letters, 28(5), 325-327.

[23] Yang, Y., Kolesov, G., Kocia, L., & Heller, E. J. (2017). Reassessing graphene absorption and emission spectroscopy. Nano letters, 17(10), 6077-6082.

[24] Xing, G., Guo, H., Zhang, X., Sum, T. C., & Huan, C. H. A. (2010). The physics of ultrafast saturable absorption in graphene. Optics express, 18(5), 4564-4573.

[25] Hwang, E. H., & Das Sarma, S. (2008). Single-particle relaxation time versus transport scattering time in a two-dimensional graphene layer. Physical Review B—Condensed Matter and Materials Physics, 77(19), 195412.