本論文探討氧化鋅耦合微共振腔且在使用光激發發光技術下所產生單模紫外雷射，兩根寬度不同的氧化鋅微米柱透過多功能探針平移台被擺置成邊靠邊以及角對角的形式去形成一個耦合共振腔，不同於一般操作在多縱模的單根氧化鋅雷射，我們利用游標尺效應來達到在耦合共振腔中選模的效果也可以有效增加自由光譜範圍，擺置邊靠邊的耦合共振腔系統可以得到側模抑制比約17.4 dB以及得到線寬約0.19nm，也用數值化分析耦合共振腔的特性，也顯示出只有單一模態能在對應到的耦合共振腔中存在，也透過有限時域差分法模擬電場在耦合微共振腔中的分佈，實驗結果也顯示出透過此方法可以有效去達成單一頻率的微共振腔雷射。

We demonstrate single-mode ultraviolet lasing from coupled ZnO microrods through optical pumping. ZnO microrods with slightly different diameters were placed side-by-side and corner-to-corner in contact to form a coupled cavity through multifunctional probe station. Unlike individual ZnO microlasers, which operate in multiple longitude mode. The mode selection mechanism is realized by the Vernier effect of coupled cavities in the microrods, which strongly expand the free space range (FSR).The side-by-side coupled cavity system obtained a side-mode-suppression ratio of 17.4 dB and line width of 0.19 nm.The resonant properties of the coupled cavities were numerically analyzed, revealing that only one mode can survive in the coupled ZnO microrods. The results indicate an accessible route to realizing single-frequency laser from microcavity lasers.

1. C. Z. Ning, Semiconductor nanowire lasers Academic Press: Burlington, (2012).
2. Y. Ma, X. Guo, X. Wu, L. Dai, and L. Tong, "Semiconductor nanowire lasers," Advances in Optics and Photonics 5, 216-273 (2013).
3. M. A. Zimmler, F. Capasso, S. Müller, and C. Ronning, "Optically pumped nanowire lasers: invited review," Semiconductor Science and Technology 25, 024001 (2010).
4. Y.-J. Lu, J. Kim, H.-Y. Chen, C. Wu, N. Dabidian, C. E. Sanders, C.-Y. Wang, M.-Y. Lu, B.-H. Li, and X. Qiu, "Plasmonic nanolaser using epitaxially grown silver film," Science 337, 450-453 (2012).
5. H. Xu, J. B. Wright, A. Hurtado, Q. Li, T.-S. Luk, J. J. Figiel, K. Cross, G. Balakrishnan, L. F. Lester, and I. Brener, "Gold substrate-induced single-mode lasing of GaN nanowires," Applied Physics Letters 101, 221114 (2012).
6. S. Gradečak, F. Qian, Y. Li, H.-G. Park, and C. M. Lieber, "GaN nanowire lasers with low lasing thresholds," Applied Physics Letters 87, 173111 (2005).
7. Q. Li, J. B. Wright, W. W. Chow, T. S. Luk, I. Brener, L. F. Lester, and G. T. Wang, "Single-mode GaN nanowire lasers," Optics Express 20, 17873-17879 (2012).
8. Y. Lu, F. Gu, C. Meng, H. Yu, Y. Ma, W. Fang, and L. Tong, "Multicolour laser from a single bandgap-graded CdSSe alloy nanoribbon," Optics Express 21, 22314-22319 (2013).
9. N. S. Han, H. S. Shim, S. Lee, S. M. Park, M. Y. Choi, and J. K. Song, "Light–matter interaction and polarization of single ZnO nanowire lasers," Physical Chemistry Chemical Physics 14, 10556-10563 (2012).
10. H. Xu, J. B. Wright, T.-S. Luk, J. J. Figiel, K. Cross, L. F. Lester, G. Balakrishnan, G. T. Wang, I. Brener, and Q. Li, "Single-mode lasing of GaN nanowire-pairs," Applied Physics Letters 101, 113106 (2012).
11. H. Li, J. Li, L. Qiang, Y. Zhang, and S. Hao, "Single-mode lasing of nanowire self-coupled resonator," Nanoscale 5, 6297-6302 (2013).
12. Y. Xiao, C. Meng, P. Wang, Y. Ye, H. Yu, S. Wang, F. Gu, L. Dai, and L. Tong, "Single-nanowire single-mode laser," Nano Letters 11, 1122-1126 (2011).
13. Y. Xiao, C. Meng, X. Wu, and L. Tong, "Single mode lasing in coupled nanowires," Applied Physics Letters 99, 023109 (2011).
14. D. L. Elliott, Ultraviolet laser technology and applications Academic press, (2014).
15. H. Gao, A. Fu, S. C. Andrews, and P. Yang, "Cleaved-coupled nanowire lasers," Proceedings of the National Academy of Sciences 110, 865-869 (2013).
16. J. B. Wright, S. Campione, S. Liu, J. A. Martinez, H. Xu, T. S. Luk, Q. Li, G. T. Wang, B. S. Swartzentruber, and L. F. Lester, "Distributed feedback gallium nitride nanowire lasers," Applied Physics Letters 104, 041107 (2014).
17. Q. Zhang, G. Li, X. Liu, F. Qian, Y. Li, T. C. Sum, C. M. Lieber, and Q. Xiong, "A room temperature low-threshold ultraviolet plasmonic nanolaser," Nature communications 5 (2014).
18. L. Rayleigh, "CXII. The problem of the whispering gallery," The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science 20, 1001-1004 (1910).
19. R. Chen, and H. D. Sun, "Single mode lasing from hybrid hemispherical microresonators," Scientific reports 2, 244 (2012).
20. R. Chen, and H. D. Sun, "Tuning whispering gallery mode lasing from self-assembled polymer droplets," Scientific reports 3, 1362 (2013).
21. J. Li, Y. Lin, J. Lu, C. Xu, Y. Wang, Z. Shi, and J. Dai, "Single Mode ZnO Whispering-Gallery Submicron Cavity and Graphene Improved Lasing Performance," ACS nano 9, 6794-6800 (2015).
22. C. P. Dietrich, "Cavity effects in polygonal resonators," (2012).
23. R. Schmidt-Grund, P. Kühne, C. Czekalla, D. Schumacher, C. Sturm, and M. Grundmann, "Determination of the refractive index of single crystal bulk samples and micro-structures," Thin Solid Films 519, 2777-2781 (2011).
24. L. H. Thomas, "The motion of the spinning electron," Nature 117, 514 (1926).
25. J. Van Vleck, "Theory of the variations in paramagnetic anisotropy among different salts of the iron group," Physical Review 41, 208 (1932).
26. C. F. Klingshirn, Semiconductor optics, Springer Science & Business Media (2012).
27. C. F. Klingshirn, A. Waag, A. Hoffmann, and J. Geurts, Zinc oxide: from fundamental properties towards novel applications, Springer Science & Business Media (2010).
28. A. Trichet, "One-dimensional polaritons in ZnO microwires: Towards onedimensional quantum degenerated gas of bosons," L'université de Grenoble (2012).
29. R. Laskowski, and N. E. Christensen, "Ab initio calculation of excitons in ZnO," Physical Review B 73, 045201 (2006).
30. S. Chichibu, T. Sota, G. Cantwell, D. Eason, and C. Litton, "Polarized photoreflectance spectra of excitonic polaritons in a ZnO single crystal," Journal of Applied Physics 93, 756-758 (2003).
31. D. Whittaker, P. Kinsler, T. Fisher, M. Skolnick, A. Armitage, A. Afshar, J. Roberts, G. Hill, and M. Pate, "Motional narrowing in semiconductor microcavities," Superlattices and Microstructures 22, 91-96 (1997).
32. J. Wiersig, "Hexagonal dielectric resonators and microcrystal lasers," Physical Review A 67, 023807 (2003).
33. J. Liu, S. Lee, Y. Ahn, J.-Y. Park, K. H. Koh, and K. H. Park, "Identification of dispersion-dependent hexagonal cavity modes of an individual ZnO nanonail," Applied Physics Letters 92, 263102 (2008).
34. Q. Duan, D. Xu, W. Liu, J. Lu, L. Zhang, J. Wang, Y. Wang, J. Gu, T. Hu, and W. Xie, "Polariton lasing of quasi-whispering gallery modes in a ZnO microwire," Applied Physics Letters 103, 022103 (2013).
35. S. O. Kasap, Optoelectronics & Photonics: Principles & Practices: International Edition, Pearson Higher Ed (2013).
36. P. Saeung, and P. P. Yupapin, "Vernier effect of multiple-ring resonator filters modeling by a graphical approach," Optical Engineering 46, 075005-075005-075006 (2007).
37. K. Oda, N. Takato, and H. Toba, "A wide-FSR waveguide double-ring resonator for optical FDM transmission systems," Journal of Lightwave Technology 9, 728-736 (1991).
38. J. Frenkel, "On the transformation of light into heat in solids. I," Physical Review 37, 17 (1931).
39. J. Gérard, B. Sermage, B. Gayral, B. Legrand, E. Costard, and V. Thierry-Mieg, "Enhanced spontaneous emission by quantum boxes in a monolithic optical microcavity," Physical Review letters 81, 1110 (1998).
40. J. Hopfield, "Theory of the contribution of excitons to the complex dielectric constant of crystals," Physical Review 112, 1555 (1958).
41. C. Sturm, H. Hilmer, R. Schmidt-Grund, and M. Grundmann, "Exciton–polaritons in a ZnO-based microcavity: polarization dependence and nonlinear occupation," New Journal of Physics 13, 033014 (2011).
42. T. Byrnes, N. Y. Kim, and Y. Yamamoto, "Exciton-polariton condensates," Nature Physics 10, 803-813 (2014).
43. M. Ahmad, and J. Zhu, "ZnO based advanced functional nanostructures: synthesis, properties and applications," Journal of Materials Chemistry 21, 599-614 (2011).
44. S. N. Mohammad, "For nanowire growth, vapor-solid-solid (vapor-solid) mechanism is actually vapor-quasisolid-solid (vapor-quasiliquid-solid) mechanism," The Journal of Chemical Physics 131, 224702 (2009).
45. C. Czekalla, C. Sturm, R. Schmidt-Grund, B. Cao, M. Lorenz, and M. Grundmann, "Whispering gallery mode lasing in zinc oxide microwires," Applied Physics Letters 92, 241102 (2008).
46. G. Griffel, "Vernier effect in asymmetrical ring resonator arrays," IEEE Photonics Technology Letters 12, 1642-1644 (2000).
47. J. Dai, C. Xu, R. Ding, K. Zheng, Z. Shi, C. Lv, and Y. Cui, "Combined whispering gallery mode laser from hexagonal ZnO microcavities," Applied Physics Letters 95, 191117 (2009).
48. X. Zhang, H. Li, X. Tu, X. Wu, L. Liu, and L. Xu, "Suppression and hopping of whispering gallery modes in multiple-ring-coupled microcavity lasers," Josa B 28, 483-488 (2011).
49. D. Porras, and C. Tejedor, "Linewidth of a polariton laser: Theoretical analysis of self-interaction effects," Physical Review B 67, 4 (2003).
50. J. Kasprzak, M. Richard, S. Kundermann, A. Baas, P. Jeambrun, J. M. J. Keeling, F. M. Marchetti, M. H. Szymanska, R. Andre, J. L. Staehli, V. Savona, P. B. Littlewood, B. Deveaud, and L. S. Dang, "Bose-Einstein condensation of exciton polaritons," Nature 443, 409-414 (2006).
51. M. W. a. I. Carusotto, "Excitations in a non-equilibrium Bose-Einstein condensate of exciton-polaritons," Physical Review letters 99, 140402 (2007).
52. D. N. Krizhanovskii, K. G. Lagoudakis, M. Wouters, B. Pietka, R. A. Bradley, K. Guda, D. M. Whittaker, M. S. Skolnick, B. Deveaud-Pledran, M. Richard, R. Andre, and L. S. Dang, "Coexisting nonequilibrium condensates with long-range spatial coherence in semiconductor microcavities," Physical Review B 80, 9 (2009).