Dissipative soliton in self-similar and all normal dispersion (ANDi) lasers has attracted much attention in recent years because of the increased intracavity and output pulse energy in fiber laser regime. The large linear up-chirp induced by the group velocity dispersion (GVD) broadens the intracavity pulse width, suppressing the peak power and nonlinear chirp that would otherwise cause wave breaking. ANDi laser is further distinguished from soliton and stretched pulse lasers in terms of the pulse formation mechanism. In the presence of large normal dispersion, the temporal pulse shape will imitate the power spectrum. As a result, a spectral filter acts as an effective saturable absorber that will suppress the pulse wings in the time domain. Stable mode-locking can be achieved if the spectral filter bandwidth, GVD, and nonlinear phase accumulation are properly designed.
In the thesis, we propose a tunable ANDi Erbium-doped fiber laser at 1.5 um wavelength. The central wavelength and spectral bandwidth are tunable by introducing an intracavity Fourier transform (FT) pulse shaper as a dynamic spectral filter. The FT pulse shaper allows for phase modulation by inserting a spatial light modulator, which may further increase the pulse energy without wave breaking.

近年來因為共振腔內和輸出能量的提高，自相似和全正色散耗散光孤子在光纖雷射領域引起廣泛的討論和注意。群速度色散所造成龐大的線性頻率分佈會展寬共振腔內脈衝的時間寬度，降低脈衝的尖峰功率，進而壓制會造成脈衝分裂崩潰的非線性效應。全正色散雷射因為其鎖膜方式而跟光孤子和伸縮脈衝光孤子有所區別。在龐大的正色散影響之下，脈衝時間上的形狀會模仿頻譜的形狀。這時候光帶通濾波器就會表現的像飽和吸收體，衰減並切除時間上脈衝的兩翼。因此當濾波器頻寬、群速度色散的大小以及非線性相位的累積經過適當得設計後便可達成一穩定的鎖膜脈衝雷射。
在本論文裡，我們提出了中心波長在1.5微米的可調式全正色散摻鉺光纖脈衝雷射。在我們的架構中，藉由在共振腔內引入傅立葉脈衝塑形器作為動態的濾波器，我們可以調整雷射的中心波長和輸出的頻寬。除此之外，在傅立葉脈衝塑形器內架設光波空間調變裝置後，我們可以調變脈衝的相位，更進一步提高脈衝的能量而不會讓脈衝崩潰。

1. D. Spence, P. Kean, and W. Sibbett, “60-fsec pulse generation from a self-mode-locked Ti:sapphire laser”, Optics Letters 16, 42 (1991).

2. D. J. Richardson, R. I. Laming, D. N. Payne, M.W. Phillips, and V. J. Matsas, “Soliton generation with passively mode-locked erbium fiber laser”, Electronics Letters 27, 730 (1991).

3. A. M. Weiner, Ultrafast Optics (Wiley, 2008).

4. F. W. Wise, A. Chong, W. H. Renninger, “High-energy femtosecond fiber lasers based on pulse propagation at normal dispersion”, Laser Photonics Review 2, 58-73 (2008).

5. G. P. Agrawal, Nonlinear Fiber Optics (Academic Press, Fourth Edition).

6. K. Tamura, J. Jacobson, H. A. Haus, E. P. Ippen, and J. G. Fujimoto, “77-fs pulse generation from a stretched-pulse mode-locked all-fiber ring laser”, Optics Letter 18, 1080 (1993).

7. D. Anderson, M. Desaix, M. Karlsson, M. Lisak, and M. L. Quiroga-Teixeiro, “Wave-breaking-free pulses in nonlinear-optical fibers”, Journal of the Optical Society of America B 10, 1185 (1993).

8. V. I. Kruglov, B. C. Thomsen, J. M. Dudley, and J. D. Harvey, “Self-Similar propagation and amplification of parabolic pulses in optical fibers”, Physical Review Letters 84, 6010–6013 (2000).

9. A. Chong, W. H. Renninger, and F.W. Wise, “All–normal-dispersion femtosecond fiber laser with pulse energy above 20 nJ”, Optics Letters 32, 2408 (2007).

10. A. Chong, J. Buckley, W. Renninger and F. Wise, “All-normal-dispersion femtosecond fiber laser”, Optics Express 14, 10095-10100 (2006).

11. N. B. Chichkov, K. Hausmann, D. Wandt, U. Morgner, J. Neumann, and D. Kracht, “High-power dissipative solitons from an all-normal dispersion erbium fiber oscillator”, Optics Letters 35, 2807-2809 (2010).

12. A. Ruehl, V. Kuhn, D. Wandt, and D. Kracht, “Normal dispersion erbium-doped fiber laser with pulse energies above 10 nJ”, Optics Express 16, 3130-3135 (2008).

13. A. Ruehl, H. Hundertmark, D. Wandt, C. Fallnich, and D. Kracht, “0.7W all-fiber Erbium oscillator generating 64 fs wave breaking-free pulses”, Optics Express 13, 6305-6309 (2005).

14. A. Chong, W. H. Renninger, F. W. Wise, “Properties of normal-dispersion femtosecond fiber lasers”, Journal of the Optical Society of America B 25, 140-148 (2008).

15. M. Hofer, M. H. Ober, F. Haberl, and M. Fermann, “Characterization of ultrashort pulse formation in passively mode-locked fiber lasers”, IEEE Journal Quantum Electronics 28, 720, (1992).