本研究旨在研究使用InGaN二極體雷射（LD）的單頻綠光雷射系統的特性。通過探測雷射輸出縱向模態隨著工作條件,包含施加電流及工作溫度的變化。我們發現當施加電流略高於閾值電流時，綠光LD為單縱模輸出。而縱向模態的數量隨著施加電流的增加而增多。依此模態分析的結果，可以定義LD的單縱模操作區域。在此工作區間內，可以完成20 MHz線寬(使用光隔絕器可達16 MHz)，15 mW輸出功率的單頻雷射光源。將該單頻操作的LD應用在在注入鎖定系統中，可以產生60 mW的雷射輸出功率，其光譜線寬為16 MHz。
此外，我們提出了一種單頻綠光InGaN外腔式二極體雷射（ECDL）的設計，其具有35 mW的輸出功率和9 MHz的線寬(使用光隔絕器可達6.5 MHz)。此ECDL為Littrow架構，其總效率約為48.5％，而波長可調區域為6 nm。我們使用光譜儀分析不同施加電流和工作溫度下的雷射光譜。最後，我們使用掃描法布里-佩羅干涉儀(SFPI)來量測ECDL的線寬及其隨工作條件的變化關係。該ECDL進一步應用在注入鎖定系統中，可產生具有6.5 MHz頻譜線寬的單頻雷射光源，而功率轉換效率可達52.7 %。

This study aims to investigate the properties of single-frequency green laser systems using InGaN laser diode (LD). By probing the longitudinal mode evolution, we found that right above the lasing threshold, the green LD emitted single longitudinal mode output. The number of the longitudinal modes increased with increasing applied current. Therefore, a single-longitudinal-mode operating regions of direct LD can be verified. And a laser source with spectral linewidth of 20 MHz and output power of 15 mW was achieved. The linewidth would be improved to be about 16 MHz with an optical isolator. This LD was further implemented in an injection locking system to generate high output power up to 60 mW with spectral linewidth of 16 MHz.
In addition, we presented a design of a single-frequency green InGaN external cavity diode laser (ECDL) with 35 mW output power and 9 MHz linewidth, which can be further improved to 6.5 MHz by implementing an optical isolator. The ECDL was in Littrow configuration, with an overall efficiency of approximately 48.5% and a wavelength tuning region of 6 nm. We used a spectrometer to analyze the laser spectrum under different applied currents and operating temperatures. Then we estimated the linewidth of the ECDL using a scanning Fabry–Perot interferometer and verified the dependence on operating conditions. This ECDL was further implemented in an injection locking system to generate a laser output with spectral linewidth as narrower as 6.5 MHz. And the power conversion ratio to injection locking mode is up to 52.7%.

References

1. N. Holonyak Jr, N. Holonyak, and S. F. Bevacqua, "Coherent ( visible) light emission from Ga(As1-xPx) junctions," Applied Physics Letters 1, 82-83 (1962).
2. E. N. Glezer, M. Milosavljevic, L. Huang, R. J. Finlay, T. H. Her, J. P. Callan, and E. Mazur, "Three-dimensional optical storage inside transparent materials," Opt. Lett. 21, 2023-2025 (1996).
3. V. Bhatia, S. J. Gregorski, D. Pikula, S. C. Chaparala, D. A. S. Loeber, J. Gollier, J. D. Gregorski, M. Hempstead, Y. Ozeki, Y. Hata, K. Shibatani, F. Nagai, N. Mori, Y. Nakabayashi, N. Mitsugi, and S. Nakano, "Efficient and compact green laser for micro-projector applications," Journal of the Society for Information Display 17, 271-277 (2009).
4. Y.-f. Tzeng, "Parametric analysis of the pulsed Nd:YAG laser seam-welding process," Journal of Materials Processing Technology 102, 40-47 (2000).
5. T. Hirogaki, H. Nakagawa, M. Hayamizu, Y. Kita, and Y. Kakino, "In-situ heat treatment system for die steels using YAG laser with a machining center," Precision Engineering 25, 212-217 (2001).
6. H. Ohta, S. P. DenBaars, and S. Nakamura, "Future of group-III nitride semiconductor green laser diodes [Invited]," J. Opt. Soc. Am. B 27, B45-B49 (2010).
7. S. L. Trokel, R. Srinivasan, and B. Braren, "Excimer Laser Surgery of the Cornea," American Journal of Ophthalmology 96, 710-715 (1983).
8. A. P. S. S. G. Participants, N. Bloembergen, C. K. N. Patel, P. Avizonis, R. G. Clem, A. Hertzberg, T. H. Johnson, T. Marshall, R. B. Miller, W. E. Morrow, E. E. Salpeter, A. M. Sessler, J. D. Sullivan, J. C. Wyant, A. Yariv, R. N. Zare, A. J. Glass, L. C. Hebel, A. P. S. C. R. Committee, G. E. Pake, M. M. May, W. K. Panofsky, A. L. Schawlow, C. H. Townes, and H. York, "Report to The American Physical Society of the study group on science and technology of directed energy weapons," Reviews of Modern Physics 59, S1-S201 (1987).
9. J. D. Dale, P. R. Smy, and R. M. Clements, "Laser Ignited Internal Combustion Engine - An Experimental Study," SAE Transactions 87, 1539-1548 (1978).
10. W. S. Grundfest, F. Litvack, J. S. Forrester, T. Goldenberg, H. J. C. Swan, L. Morgenstern, M. Fishbein, I. Stuart McDermid, D. M. Rider, T. J. Pacala, and J. B. Laudenslager, "Laser ablation of human atherosclerotic plaque without adjacent tissue injury," Journal of the American College of Cardiology 5, 929-933 (1985).
11. J. PELAGALLI, C. B. GIMBEL, R. T. HANSEN, A. SWETT, and D. W. W. II, "Investigational Study of the Use of Er:YAG Laser Versus Dental Drill for Caries Removal and Cavity Preparation— Phase I," Journal of Clinical Laser Medicine & Surgery 15, 109-115 (1997).
12. R. Kaiser, and B. Huttl, "Monolithic 40-GHz Mode-Locked MQW DBR Lasers for High-Speed Optical Communication Systems," IEEE Journal of Selected Topics in Quantum Electronics 13, 125-135 (2007).
13. D. A. Rusak, B. C. Castle, B. W. Smith, and J. D. Winefordner, "Fundamentals and Applications of Laser-Induced Breakdown Spectroscopy," Critical Reviews in Analytical Chemistry 27, 257-290 (1997).
14. T. L. Koch, and U. Koren, "Semiconductor lasers for coherent optical fiber communications," Journal of Lightwave Technology 8, 274-293 (1990).
15. P. Brumer, and M. Shapiro, "Laser Control of Chemical Reactions," Scientific American 272, 56-63 (1995).
16. V. Scarani, A. Acín, G. Ribordy, and N. Gisin, "Quantum Cryptography Protocols Robust against Photon Number Splitting Attacks for Weak Laser Pulse Implementations," Physical Review Letters 92, 057901 (2004).
17. D. E. J. G. J. Dolmans, D. Fukumura, and R. K. Jain, "Photodynamic therapy for cancer," Nature Reviews Cancer 3, 380 (2003).
18. K. C. Harvey, and C. J. Myatt, "External-cavity diode laser using a grazing-incidence diffraction grating," Opt. Lett. 16, 910-912 (1991).
19. W. H. Bragg, "Bakerian Lecture: X-Rays and Crystal Structure," Philosophical transactions - Royal Society. Mathematical, Physical and engineering sciences 215, 253-274 (1915).
20. H.-C. Chui, M.-S. Ko, Y.-W. Liu, T. Lin, J.-T. Shy, S.-Y. Shaw, R. V. Roussev, and M. M. Fejer, "Frequency stabilization of a frequency-doubled 197.2THz distributed feedback diode laser on rubidium 5S1/2→7S1/2 two-photon transitions," Optics and Lasers in Engineering 44, 479-485 (2006).
21. A. L. Glebov, O. Mokhun, A. Rapaport, S. Vergnole, V. Smirnov, and L. B. Glebov, "Volume Bragg gratings as ultra-narrow and multiband optical filters," in SPIE Photonics Europe(SPIE2012), p. 11.
22. T.-y. Chung, Y.-H. Hsieh, and Y.-C. Hsiao, "PQ:DMNA/PMMA, a new material for recording volume Bragg grating for laser spectrum narrowing," in Frontiers in Optics / Laser Science(Optical Society of America, Washington, DC, 2018), p. JW3A.133.
23. T. Hosoya, M. Miranda, R. Inoue, and M. Kozuma, "Injection locking of a high power ultraviolet laser diode for laser cooling of ytterbium atoms," Review of Scientific Instruments 86, 073110 (2015).
24. C. J. H. Pagett, P. H. Moriya, R. C. Teixeira, R. F. Shiozaki, M. Hemmerling, and P. W. Courteille, "Injection locking of a low cost high power laser diode at 461 nm," Review of Scientific Instruments 87, 053105 (2016).
25. C. Eichler, S. S. Schad, F. Scholz, D. Hofstetter, S. Miller, A. Weimar, A. Lell, and V. Härle, "Observation of temperature-independent longitudinal-mode patterns in violet-blue InGaN-based laser diodes," IEEE Photonics Technology Letters 17, 1782-1784 (2005).
26. W. Al-Basheer, A. Aljalal, and K. Gasmi, "Evolution of blue laser diode spectral lines with applied current in the range 446–448 nm," Opt. Sensors 2015, 9506 (2015).
27. W. Al-Basheer, A. Aljalal, K. Gasmi, and T. O. Adigun, "High-resolution investigation of longitudinal modes of a GaN-based blue laser diode," in Proceedings of SPIE - The International Society for Optical Engineering(2017).
28. A. Avramescu, T. Lermer, J. Müller, S. Tautz, D. Queren, S. Lutgen, and U. Strauß, "InGaN laser diodes with 50 mW output power emitting at 515 nm," Applied Physics Letters 95, 071103 (2009).
29. A. Adrian, L. Teresa, M. Jens, E. Christoph, B. Georg, S. Matthias, L. Stephan, and S. Uwe, "True Green Laser Diodes at 524 nm with 50 mW Continuous Wave Output Power on c -Plane GaN," Applied Physics Express 3, 061003 (2010).
30. T. Hager, U. Strauß, C. Eichler, C. Vierheilig, S. Tautz, G. Brüderl, B. Stojetz, T. Wurm, A. Avramescu, A. Somers, J. Ristic, S. Gerhard, A. Lell, S. Morgott, and O. Mehl, "Power blue and green laser diodes and their applications," in SPIE OPTO(SPIE2013), p. 8.
31. T. Cao, C. Wei, and L. Mao, "Ultrafast tunable chirped phase-change metamaterial with a low power," Optics Express 23, 4092-4105 (2015).
32. A. Agnesi, S. Dell’Acqua, G. C. Reali, P. G. Gobbi, and D. Ragazzi, "Design and characterization of a diode-pumped, single longitudinaland transverse mode, intracavity-doubled cw Nd:YAG laser," Appl. Opt. 36, 597-601 (1997).
33. A. Jechow, M. Schedel, S. Stry, J. Sacher, and R. Menzel, "Highly efficient single-pass frequency doubling of a continuous-wave distributed feedback laser diode using a PPLN waveguide crystal at 488 nm," Opt. Lett. 32, 3035-3037 (2007).
34. M. H. Hu, N. Hong Ky, S. Kechang, L. Yabo, N. J. Visovsky, L. Xingsheng, N. Nishiyama, S. Coleman, L. C. Hughes, J. Gollier, W. Miller, R. Bhat, and Z. Chung-En, "High-power high-Modulation-speed 1060-nm DBR lasers for Green-light emission," IEEE Photonics Technology Letters 18, 616-618 (2006).
35. H. Lu, J. Su, Y. Zheng, and K. Peng, "Physical conditions of single-longitudinal-mode operation for high-power all-solid-state lasers," Opt. Lett. 39, 1117-1120 (2014).
36. C. Zhang, H. Lu, Q. Yin, and J. Su, "Continuous-wave single-frequency laser with dual wavelength at 1064 and 532 nm," Appl. Opt. 53, 6371-6374 (2014).
37. D. Ding, X. Lv, X. Chen, F. Wang, J. Zhang, and K. Che, "Tunable high-power blue external cavity semiconductor laser," Optics & Laser Technology 94, 1-5 (2017).
38. B. Li, J. Gao, A. Yu, S. Luo, D. Xiong, X. Wang, and D. Zuo, "500mW tunable external cavity diode laser with narrow line-width emission in blue-violet region," Optics & Laser Technology 96, 176-179 (2017).
39. T. Weig, T. Hager, G. Brüderl, U. Strauss, and U. T. Schwarz, "Longitudinal mode competition and mode clustering in (Al,In)GaN laser diodes," Optics Express 22, 27489-27503 (2014).
40. Y. C. Lee, H. C. Chui, Y. Y. Chen, Y. H. Chang, and C. C. Tsai, "Effects of light on cesium 6S-8S two-photon transition," Optics Communications 283, 1788-1791 (2010).
41. B. J. Bloom, T. L. Nicholson, J. R. Williams, S. L. Campbell, M. Bishof, X. Zhang, W. Zhang, S. L. Bromley, and J. Ye, "An optical lattice clock with accuracy and stability at the 10−18 level," Nature 506, 71 (2014).
42. K. Kaduki, T. Yosuke, K. Mitsutaka, T. Yoshiro, and Y. Tsutomu, "Injection-Locking of Blue Laser Diodes and Its Application to the Laser Cooling of Neutral Ytterbium Atoms," Japanese Journal of Applied Physics 42, 5059 (2003).
43. S. D. Badger, I. G. Hughes, and C. S. Adams, "Hyperfine effects in electromagnetically induced transparency," Journal of Physics B: Atomic, Molecular and Optical Physics 34, L749 (2001).
44. M. H. M. Shamim, T. K. Ng, B. S. Ooi, and M. Z. M. Khan, "Tunable self-injection locked green laser diode," Opt. Lett. 43, 4931-4934 (2018).
45. M. H. M. Shamim, M. A. Shemis, C. Shen, H. M. Oubei, T. K. Ng, B. S. Ooi, and M. Z. M. Khan, "Investigation of Self-Injection Locked Visible Laser Diodes for High Bit-Rate Visible Light Communication," IEEE Photonics Journal 10, 1-11 (2018).
46. A. E. Siegman, Lasers (University Science Books, 1986).
47. R. Lang, and K. Kobayashi, "External optical feedback effects on semiconductor injection laser properties," IEEE Journal of Quantum Electronics 16, 347-355 (1980).
48. A. S. Arnold, J. S. Wilson, and M. G. Boshier, "A simple extended-cavity diode laser," Review of Scientific Instruments 69, 1236-1239 (1998).
49. C. J. Hawthorn, K. P. Weber, and R. E. Scholten, "Littrow configuration tunable external cavity diode laser with fixed direction output beam," Review of Scientific Instruments 72, 4477-4479 (2001).
50. S. Lecomte, E. Fretel, G. Mileti, and P. Thomann, "Self-aligned extended-cavity diode laser stabilized by the Zeeman effect on the cesium D2 line," Appl. Opt. 39, 1426-1429 (2000).
51. K. I. Martin, W. A. Clarkson, and D. C. Hanna, "3 W of single-frequency output at 532 nm by intracavity frequency doubling of a diode-bar-pumped Nd:YAG ring laser," Opt. Lett. 21, 875-877 (1996).
52. T. Cao, C. Wei, and L. Mao, "Numerical study of achiral phase-change metamaterials for ultrafast tuning of giant circular conversion dichroism," Scientific Reports 5 (2015).
53. T. Cao, C. Wei, R. E. Simpson, L. Zhang, and M. J. Cryan, "Fast Tuning of Double Fano Resonance Using A Phase-Change Metamaterial Under Low Power Intensity," Scientific Reports 4, 4463 (2014).
54. M. Chi, O. B. Jensen, and P. M. Petersen, "Tuning range and output power optimization of an external-cavity GaN diode laser at 455  nm," Appl. Opt. 55, 2263-2269 (2016).
55. W.-C. Lin, "The research of single-frequency external cavity green laser," in Department of Photonics, (National Cheng Kung University, 2017).
56. I. Bayrakli, "Breath analysis using external cavity diode lasers: a review," (SPIE2017), p. 15.
57. I.-H. Bae, H. S. Moon, S. K. Kim, S.-N. Park, and D.-H. Lee, "Optical injection locking of a singly resonantcontinuous-wave optical parametric oscillator," Opt. Lett. 38, 597-599 (2013).
58. E. B. Kim, W.-K. Lee, C. Y. Park, D.-H. Yu, and S. E. Park, "Narrow linewidth 578 nm light generation using frequency-doubling with a waveguide PPLN pumped by an optical injection-locked diode laser," Optics Express 18, 10308-10314 (2010).
59. T. Shimasaki, E. R. Edwards, and D. DeMille, "Injection-locking of a fiber-pigtailed laser to an external cavity diode laser via fiber optic circulator," (2018).
60. T. Gavara, T. Ohashi, Y. Sasaki, T. Kawashima, H. Hamano, R. Yoshizaki, Y. Fujimura, K. Yoshii, C. Ohae, and M. Katsuragawa, "Dual-frequency injection-locked continuous-wave near-infrared laser," Opt. Lett. 41, 2994-2997 (2016).