近年來光通訊產業與生醫光電的蓬勃發展，使通訊傳輸的頻寬需求增加，以及無水光纖技術突破而使光通訊用的可用頻寬拓展為1.3-1.6 μm。以雷射加熱基座生長法生長的Cr4+:YAG雙纖衣晶體光纖(double-clad crystal fiber; DCF)，利用雷射激發可產生涵蓋整個通訊波段(1.3-1.6 μm)的自發輻射頻譜，適合發展生醫檢測光源(optical coherence tomography; OCT)、寬頻光放大器、放大自發輻射(amplified spontaneous emission)光源及可調波長固態雷射(tunable solid-state laser)。

本論文為使用電子槍於摻鉻釔鋁石榴石雙纖衣光纖端面鍍上介電材質薄膜，並且改善膜層品質、增加雷射輸出端之穿透率設計以及採用高功率雷射之膜層設計。光放大器部分，將晶體光纖一端製鍍高反射膜層使訊號達到雙次傳輸，在雙向泵浦且雙次傳輸架構下產生訊號增益為 3.0 dB，插入損耗降為3.0 dB，系統淨增益達到 0 dB。雷射方面，於晶體光纖兩端製鍍上光學薄膜，形成穩定雷射共振腔，並且增加輸出端之穿透率，在室溫下雷射功率閾值為 31.2 mW，斜率效率達到 7.5%。

Recently, with the escalating demands for optical communications, the need for bandwidth in optical communication network has increased. The technology breakthrough indry fiber fabrication opens the possibility for fiber bandwidth form 1.3 to 1.6 μm. Cr4+:YAG double-clad crystal fiber (DCF) grown by the co-drawing laser-heated pedestal growth method has a strong spontaneous emission spectum form 1.3 to 1.6 μm. Such fiber is therefore, eminently suitable for optical coherence tomography (OCT), broadband optical amplifier, amplifier spontaneous emission (ASE) light source, and tunable solid-state laser applications.

In this thesis, multilayer dielectric thin films were directly deposited by E-gun coating onto the end faces of the Cr4+:YAG DCF. To improve the thin-film quality, to increase transmittance of laser output, and to design for the high power laser. For broadband optical amplifier in dual-pump and double-pass scheme, a 3.0-dB gross gain, a 3.0-dB insertion loss, and a 0-dB net gain at 1.4-μm signal wavelength have been successfully developed with HR coating onto one of the Cr4+:YAG DCF end faces. In addition, we have successfully developed the Cr4+:YAG DCF laser by direct HR coatings onto fiber end faces and increase transmittance of laser output. A record-low threshold of 31.2 mW with a slope efficiency of 7.5% was achieved at room temperature.

中文摘要 i
英文摘要 ii
致謝 iii
目錄 iv
圖目錄 vi
表目錄 ix

第一章 緒論 1
第二章 薄膜基本原理 3
2.1 光學薄膜的特性與膜矩陣 3
2.2 光學薄膜材料特性與光學常數分析 8
2.2.1 光學薄膜材料特性 8
2.2.1 薄膜光學常數分析 10
2.3 膜成長理論 16
2.4 光學薄膜設計公式及原理 18
第三章 元件製備、電子槍蒸鍍系統架構及量測儀器 24
3.1 電子槍蒸鍍系統 24
3.1.1 真空系統 24
3.1.2 電子槍系統 26
3.1.3 監控系統 29
3.2 光學薄膜量測技術 32
3.2.1 光譜量測儀 32
3.2.2 原子力顯微鏡 33
3.3 晶體光纖生長架構與方法 34
3.4 樣品包覆及端面處理 40
3.4.1 光放大器及雷射樣品製備 40
3.4.2 Cr4+:YAG雙纖衣晶體光纖之散熱封裝 45
第四章 Cr4+:YAG雙纖衣晶體光纖光放大器之端面鍍膜與光學 特性量測 48
4.1 Cr4+:YAG雙纖衣晶體光纖之光譜特性 48
4.1.1 Cr4+:YAG晶體之結構與特性 48
4.1.2Cr4+:YAG的能階模型與吸收及放射頻譜 52
4.2 薄膜於晶體光纖端面出現之問題與品質改善 55
4.3 光放大器之增益量測 64
第五章 Cr4+:YAG雙纖衣晶體光纖雷射之端面鍍膜與光學特性量測 70
5.1 光學薄膜電場分佈分析 70
5.2 高功率雷射之膜層設計 72
5.3 雷射之特性量測 75
第六章 結論與未來方向 82

參考文獻 83
中英對照表 86

[1] M. L. Fulton, “Application of ion assisted deposition using a gridless end-Hall ion source for volume manufacturing of thin-film optical filter,” Proceedings of SPIE 2253, 374 (1994).
[2] J. R. McNeil, A. C. Barron, S. R. Wilson, and W. C. Herrmann, “Ion- assisted deposition of optical thin film: low energy vs high energy bombardment,” Applied Optics 23, 552 (1984).
[3] H. Kuster and J. Ebert, “Activated reactive evaporation of TiO2 layers and their absorption indices,” Thin Solid Films 70, 43 (1980).
[4] J. J. McNally, G. A. Al-Jumaily, and J. R. McNeil, “Ion-assisted deposition of Ta2O5 and Al2O3 thin film,” Journal of Vacuum Science Technology 3, 437 (1986).
[5] G. A. Al-Jumaily, J. J. McNally, and J. R. McNeil, “Effect of ion assisted deposition on optical scatter and surface microstructure of thin films,” Journal of Vacuum Science Technology 3, 651 (1985).
[6] F. Flory, Emile Pelletier, G. albrand, and Y. Hu, “Surface optical coatings by ion assisted deposition techniques: study of uniformity,” Applied Optics 28, 2952 (1989).
[7] J. R. McNeil, G. A. Al-Jumaily, K. C. Jungling, and A. C. Barron, “Properties of TiO2 and SiO2 thin film deposited using ion assisted deposition,” Applied Optics 24, 486 (1985).
[8] D. T. Wei, “ Ion beam interference coatings for ultralow optical loss,” Applied Optics 28, 2813 (1989).
[9] 李正中，“薄膜光學與鍍膜技術”， 3rd edition (藝軒出版社，2002)。
[10] Y. Y. Liou, ”Determination of the optical constant profiles of thin weakly absorbing inhomogeneous films,” Japanese Journal of Applied Physics 34, 1952 (1995).
[11] R. Swanepoel, “Determination of the thickness and optical constants of amorphous silicon,” Journal of Physics E: Scientific Instruments 16, 1214, (1983).
[12] J. A. Thornton, “Influence of apparatus geometry and deposition conditions on the structure and topography of thick sputtered coatings,” Journal of Vacuum Science Technology 11, 666 (1974).
[13] K. H. Guenther, “Physical and chemical aspects in the application of thin films on optical elements,” Applied Optics 23, 3612 (1984).


[14] U. Kaiser, M. Adamik, G. Safran, P. B. Barna, S. Laux, and W. Richter, “Growth structure investigation of MgF2 and NdF3 films grown by molecular beam deposition on CaF2(111) substrates,” Thin Solid Films 280, 5 (1996).
[15] Epstein L. I., “The design of optical filter”,J. Opt. Soc. Am. 42,806-810
(1952)
[16] 呂登復，“實用真空技術”，國興出版，民國九十一年。
[17] 吳秀菁，汪若文，林美吟，“儀器總覽-材料分析儀器”， 行政院國家科學委員會精密儀器發展中心，民國八十七年。
[18] I. T. Sorokina, S. Naumov, E. Sorokin, and E. Wintnter, “Directly diode-pumped tunable continuous-wave room-temperature Cr4+:YAG laser,”Optics Letter 24,1578-1580(1999)
[19] G. A. Magel, M. M. Fejer, and R. L. byer, “Quasi-phase-matched second harmonic generation of blue light in periodically LiNbO3,” Applied Physics Letters 56, 108 (1990).
[20] D. B. Gasson, and B. Cockayne, “Oxide crystal growth using gas laser,” Materials Science 5, 100 (1970).
[21] M. A. Gulgun, W. Y. Ching, Y. N. Xu, and M. Ruhle, “Electron states of YAG probed by energy-loss near-edge spectrometry and ab initio calculations,” Phil. Mag. B, vol. 79, pp. 921-940, 1999.
[22] H. Eilers, W. M. Dennis, W. M. Yen, S. Kuck, K. Peterman, G. Huber, and W. Jia, “Performance of a Cr:YAG laser,” IEEE J. Quant. Electron., vol. 29, pp. 2508-2512, 1993.
[23] B. M. Tissue, W. Jia, L. Lu, and W. M. Yen, “Coloration of chromium-doped yttrium aluminum garnet single-crystal fibers using a divalent codopant,” J. Appl. Phys., vol. 70, pp. 3775-3777, 1991.
[24] S. Kuck, K. Petermann, and G. Huber, “Spectroscopic investigation of the Cr4+-center in YAG,” OSA Proceedings on Advanced Solid-State Lasers, vol. 10, pp. 92-94, 1991.
[25] A. Sennaroglu, “Analysis and optimization of lifetime thermal loading in continuous-wave Cr4+-doped solid-state lasers,” J. Opt. Soc. Am., vol. 18, pp. 1578-1586, 2001.
[26] 朱正煒, “光學薄膜設計及電場行為” ，國立中央大學光電工程研究所碩士論文，1985年。
[27] D. Milam, W. H. Lowdermilk, F. Rainer, J. E. Swain, C. K. Carniglia, and T. T. Hart, “Influence of deposition parameters on laser-damage threshold of silica-tantala AR coatings,” Applied Optics 21, 3689 (1982).
[28] O. Arnon and P. Baumeister, “Electric field distribution and the reduction of laser damage in multilayers,” Applied Optics 19, 1853 (1980)
[29] E. Hucker, H. Lauth, and P. Weissbrodt, “Review of structural influence on the laser damage threshold of oxide coatings,” Proceedings of SPIE 2714, 316 (1996).
[30] S. C. Seitel and J. O. Porteus, “Laser damage round-robin testing (1.06-μm)
with 13-nsec pulse duration and 40-μm spot size,” Applied Optics 23, 3767
(1984).
[31] K. Rajasree, P. Radhakrishnan, V. P. N. Nampoori, and C. P. G. Vallabhan,
“Determination of the laser-induced damage threshold of bulk polymer
samples at 1.06 μm using the pulsed photothermal deflection technique,”Laser Division, Department of Physics, Cochin University of Science and Technology 4, 591 (1993).
[32] G. A. Magel, M. M. Fejer, and R. L. byer, “Quasi-phase-matched second harmonic generation of blue light in periodically LiNbO3,” Applied Physics Letters 56, 108 (1990).
[33] D. B. Gasson, and B. Cockayne, “Oxide crystal growth using gas laser,”Materials Science 5, 100 (1970).
[34] C. C. Lai, H. J. Tsai, K. Y. Huang, K. Y. Hsu, Z. W. Lin, K. D. Ji, W. J.Zhuo, and S. L. Huang, “Cr4+:YAG double-clad crystal fiber laser,” Optics Letters 33,2919(2008)