[1] [1] Bonk R, Geng D, Khotimsky D A, et al. 50G-PON: the first ITU-T higher-speed pon system [J]. IEEE Communications Magazine, 2022, 60(3): 48-54.

[2] [2] Zhang D Z, Liu D K, Wu X M, et al. Progress of ITU-T higher speed passive optical network (50G-PON) standardization [J]. Journal of Optical Communications and Networking, 2020, 12(10): 99-108.

[4] [4] Wang Z C, Amin Abbasi, Utsav Dave, et al. Novel light source integration approaches for silicon photonics [J]. Laser & Photonics Reviews, 2017, 11(4): 1700063.

[5] [5] Ogita S, Hirano M, Soda H, et al. Dependence of spectral line width of DFB lasers on facet Reflectivity [J]. Electronics Letters, 2007, 23(7): 347-349.

[8] [8] Lee B G, Belkin M A, Pflugl C, et al. DFB quantum cascade laser arrays [J]. IEEE Journal of Quantum Electronics, 2009, 45(5): 554-565.

[9] [9] Wang D B, Zhang J C, Cheng F M, et al. Stable single-mode operation of distributed feedback quantum cascade laser by optimized reflectivity facet coatings [J]. Nanoscale Research Letters, 2018, 13(1): 37.

[12] [12] Frdric G. On the effects of an antireflection coating impairment on the sensitivity to optical feedback of AR/HR semiconductor DFB lasers [J]. IEEE Journal of Quantum Electronics, 2009, 45(6): 720-729.

[14] [14] Kaneko T, Akao N, Hara N, et al. In situ ellipsometry analysis on formation process of Al2O3-Ta2O5 films in Ion beam sputter deposition [J]. Chinese Chemical Letters, 2005, 26(10): 1383-1385.

[16] [16] Crooks D, Cagnoli G, Fejer M M, et al. Experimental measurements of mechanical dissipation associated with dielectric coatings formed using SiO2, Ta2O5 and Al2O3 [J]. Classical & Quantum Gravity, 2006, 23(15): 4953.

[18] [18] Jin Y, Ren C S, Yang L, et al. Atmospheric pressure plasma jet in Ar and O2/Ar mixtures: properties and high performance for surface cleaning [J]. Plasma Science and Technology, 2013, 15(12): 1203-1208.

[20] [20] Kim S T, Kim B G. Analysis of single-mode yields above threshold for complex-coupled distributed feedback lasers with asymmetric facet reflectivities [J]. JOSA B, 2005, 22(5): 1010-1015.

[21] [21] Heikki V, Topi U, Mihail Dumitrescu. Simulation studies of DFB laser longitudinal structures for narrow linewidth emission [J]. Optical and Quantum Electronics, 2017, 49(4): 160.