本論文將設計和模擬分析一摻鐿全光纖式Q與增益切換雷射系統，並極大化其輸出功率。此雷射系統架構使用摻雜鐿的雙披覆增益光纖以及摻雜鐿的飽和吸收體光纖來藉以產生高功率的脈衝雷射，並利用增益切換的方式來達成雙波長光子脈衝雷射。論文中將會利用Matlab軟體來模擬在改變Q切換波長、增益切換波長、光纖光柵反射率、飽和吸收體長度來進行討論在各種情況下的輸出特性，並且在文中推導有關雙波長光子所需的方程式來對應其理論以及結果的關聯；在鐿原子方面，我們將根據其材料的放射及吸收頻譜來模擬，配上適當波長的共振腔並使用Q與增益切換的方式產生1~1.1 μm雷射。

The purpose of the study is to analyze and numerically optimize a passively saturable-absorber Q- and gain-switched Yb3+ all-fiber laser system. By use of a Yb-doped double-clad fiber as the gain medium and a Yb-doped single-cladding fiber as the saturable-absorber, a Q- and gain-switched dual-wavelength pulsed laser system with high power output could be achieved. The parameters of the Q- and gain-switching wavelengths, the reflectivity of the output coupler, and the absorption strength of the saturable absorber were simulated and analyzed in Matlab, based on the rate equations derived in Chap. 2. Ideally, laser pulses at a broad Yb emission band of 1-1.1 m could be achieved with suitable fiber Bragg gratings (FBG).

[1] Schawlow, A. L., C. H. Townes, Infrared and optical masers. Phys.Rev.112:1940(1958)
[2] Maiman, T. H., Stimulated optical radiation in ruby masers. Nature 187:493(1960)
[3] F.J. McClung, and R. W. Hellwarth, “Giant optical Pulsation from ruby,”J. Appl. Phys. Vol.33, 828-829(1962)
[4] R. C. Benson, R. D. Goodwin and M. R. Mirarchi, NEREM Record 4, 34, (1962).
[5] D. W. Hunang, W. F. Liu, and C. C. Yang, “Q-switched all-fiber laser with an acoustically modulated fiber attenuator,” IEEE Photon. Technol. 12, 1153-1155 (2000).
[6] D. Zalvidea, N. A. Russo, R. Duchowicz, M. Delgado-Pinar, A. Diez, J. L. Cruz, and M. V. Andres, “High repetition rate acoustic-induiced Q-switched all-fiber laser” Opt. commum. 244, 315-319 (2005).
[7] M. Delgado-Pinar, D. Zalvidea, A. Diez, P. Perez-Millan, and M. V. Andres, “Q-switching of an all-fiber laser by acousto-optic modulation of a fiber Bragg grating,” Opt. Express 14, 1106-1112 (2006).
[8] P. Roy, D. Pagnoux, L. Mouneu and T. Midavaine, “High efficiency 1.53-µm all-fibre pulsed source based on a Q-switched erbium doped fibre ring laser,” Electron. Lett. 33, 1317-1318 (1997).
[9]A. R. Newberry, Br. J. Appl. Phys. vol. 1, p. 1849, (1968).
[10] L. Tordella, H. Dejellout, B. Dussardier, A. Saissy, and G. Monnom, “High repetition rate passively Q-switched Nd3+:Cr4+ all fibre laser,” Electron. Lett. 39(18), 1307–1308 (2003).
[11] T.-Y. Tsai, Y.-C. Fang, and S.-H. Hung, “Passively Q-switched erbium all-fiber lasers by use of thulium-doped saturable-absorber fibers,” Opt. Express 18(10), 10049–10054 (2010).
[12] S. D. Jackson, “Passively Q-switched Tm(3+)-doped silica fiber lasers,” Appl. Opt. 46(16), 3311–3317 (2007).
[13] P. Adel, M. Auerbach, C. Fallnich, S. Unger, H.-R. Müller, and J. Kirchhof, “Passive Q-switching by Tm3+ codoping of a Yb3+-fiber laser,” Opt. Express 11(21), 2730–2735 (2003).
[14] A. A. Fotiadi, A. S. Kurkov, and I. M. Razdobreev, “All-fiber passively Q-switched Ytterbium laser,” 2005 Conference on Lasers and Electro-Optics Europe, p. 515.

[15] A. S. Kurkov, E. M. Sholokhov, and O. I. Medvedkov, “All fiber Yb-Ho pulsed laser,” Laser Phys. Lett. 6(2), 135–138 (2009).
[16]V. V. Dvoyrin, V. M. Mashinsky, and E. M. Dianov, “Yb-Bi pulsed fiber laser,” Opt. Lett. 32, 451-453 (2007).
[17] T.-Y. Tsai, Y.-C. Fang, Z.-C. Lee, and H.-X. Tsao, “All-fiber passively Q-switched erbium laser using mismatch of mode field areas and a saturable-amplifier pump switch,” Opt. Lett. 34(19), 2891–2893 (2009).
[18] T. Y. Tsai, Y. C. Fang, “A self-Qswitched all-fiber erbium laser at 1530nm using auxiliary 1570nm erbium laser”,Opt Express 17,21629-21633(2009).
[19] A. Siegman, “Passive Saturable Absorber Q-switching,” in Lasers(University Science Books, 1986), Chap. 26.3, pp. 1024–1033.
[20] K. C. Kao, G. A. Hockham "Dielectric-fibre surface waveguides for optical frequencies," Proc. IEEE 113 (7): 1151–1158. (1966).
[21] K.O. Hill, “Photosensitivity in optical fiber waveguides: application to reflection fiber fabrication,” Appl. Phys. Lett. 32: 647. (1978).
[22]T. Y. Tsai, Y. C. Fang and S. H. Hung, “Passively Q-switched erbium all-fiber by use of Thulium-doped saturable-absorable fibers”,Opt Express 18,10049-10052(2010).
[23] L. A. Zenteno, E. Snitzer, H. Po, R. Tumminelli, and F. Hakimi “Gain switching of a Nd&3-doped fiber laser” Opt. Lett. Vol. 14, No. 13, (1989).
[24] M. Eichhorn “Development of a high-pulse-energy Q-switched Tm-doped double-clad fluoride fiber laser and its application to the pumping of mid-IR lasers,” Opt. Lett. Vol. 32, No. 9, (2007).
[25] E. Snitzer, L. Tumminelli, F. Hakimi, N.M. Chu, and T. Haw (1989). "Doubly clad high brightness Nd fiber laser pumped by GaAlAs phased array". Optical Fiber Communication Conference. PD7.
[26] Y. Jeong, J. Sahu, D. Payne, and J. Nilsson. "Ytterbium-doped large-core fiber laser with 1.36 kW continuous-wave output power". Optics Express 12 (25): 6088–6092(2004).
[27] R. Paschotta, J. Nilsson, Anne C. Tropper, and David C. Hanna., “Ytterbium-doped fiber amplifiers”, IEEE J. Quantum Electron. 33 (7), 1049 (1997)