[1] V. N. Kurlov, Sapphire: Properties, Growth, and Applications, Elsevier, Oxford, 2016.
[2] R. G. Hunsperger, Integrated Optics: Theory and Technology, Springer, Berlin Heidelberg, 1984.
[3] S. E. Miller, Bell System Technical Journal 48, 2059 (1969).
[4] C. Shi, L. Zhang, J. Hong, F. Zhang, S. Pan and Y. Hang, Journal of Synthetic Crystals 44, 2652 (2015). (in Chinese)
[5] X. Bian, M. Chen and G. Li, Laser & Optoelectronics Progress 53, 051404 (2016). (in Chinese)
[6] Cai Zhixiang, Gao Xunyin, Yang Wei, Sun Zhilong and Ye Yumei, Laser & Optoelectronics Progress 52, 081403 (2015). (in Chinese)
[7] Y. Zhou, G. Pan, H. Gong, X. Shi and C. Zou, Colloids and Surfaces A: Physicochemical and Engineering Aspects 513, 153 (2017).
[8] C-T Kuo, L-H Hsu, B-H Huang, H-C Kuo, C-C Lin and Y-J Cheng, Applied Optics 55, 7387 (2016).
[9] D. Wu, P. Ma, B. Liu, S. Zhang, J. Wang and J. Li, Journal of Semiconductors 37, 104003 (2016).
[10] W.C. Ke, C.Y. Chiang, W. Son and F.W. Lee, Applied Surface Science 456, 967 (2018).
[11] C. B. Schaffer, A. Brodeur and E. Mazur, Measurement Science and Technology 12, 1784 (2001).
[12] A. P. Joglekar, H. Liu, G. J. Spooner, E. Meyh?fer, G. Mourou and A. J. Hunt, Applied Physics B 77, 25 (2003).
[13] A. G. Rickman, G. T. Reed and F. Namavar, Journal of Lightwave Technology 12, 1771 (1994).
[14] C. Huang, G. Zhang and J. Liu, Journal of Optoelectronics ·Laser 13, 20 (2002). (in Chinese)
[15] F. Ladouceur, Journal of Lightwave Technology 15, 1020 (1997).
[16] K. P. Chen, M. J. Li, M. Li, S. M. Garner and S. Huang, Optics Express 23, 22532 (2015).
[17] M. Melchiorri, N. Daldosso, F. Sbrana, L. Pavesi, G. Pucker, C. Kompocholis, P. Bellutti and A. Lui, Applied Physics Letters 86, 121111 (2005).
[18] N. Daldosso, M. Melchiorri, F. Riboli, M. Girardini, G. Pucker, M. Crivellari, P. Bellutti, A. Lui and L. Pavesi, Journal of Lightwave Technology 22, 1734 (2004).
[19] W. Longde, Z. Tong, Z. Xiaoyang, L. Ruozhou and W. Luning, Journal of Southeast University ( English Edition) 29, 152 (2013).
[20] D. Lee, M. Yang, C. Huang and J. Dai, IEEE Photonics Technology Letters 26, 2107 (2014).
[21] Z. Tian, Z. Yu, B. Liu and A. Wang, Optics Letters 41, 195 (2016).
[22] B. Zhang and M. Kahrizi, High-Temperature Bragg Grating Waveguide Sensor, International Conference on MEMS, NANO and Smart Systems, 400 (2003).