[1] M. C. Larson. Widely tunable semiconductor lasers. Optical Fiber Communication Conference, Tu2H.1(2014).

[2] M. Seimetz. Laser linewidth limitations for optical systems with high-order modulation employing feed forward digital carrier phase estimation. Optical Fiber Communication/National Fiber Optic Engineers Conference, OTuM2(2008).

[3] C. Y. Ye. Tunable External Cavity Diode Lasers(2004).

[4] A. Daiber. Narrow-linewidth tunable external cavity laser for coherent communication. Photonics Conference, 447-448(2014).

[5] M. C. Amann, R. Schimpe. Excess linewidth broadening in wavelength-tunable laser diodes. IEEE Electron. Lett., 26, 279-280(1990).

[6] S. Nakagawa, G. Fish, A. Dahl, P. Koh, C. Schow, M. Mach, L. Wang, R. Yu. Phase noise of widely-tunable SG-DBR laser. Optical Fiber Communications Conference, ThF2(2003).

[7] R. T. Watts, K. Shi, Y. L. Yu, L. P. Barry. Detailed experimental phase noise characterization of Y-branch lasers for use in coherent communication systems. Optical Fiber Communication Conference & Exposition / National Fiber Optic Engineers Conference, JW2A.32(2013).

[8] H. Ishii, K. Kasaya, H. Oohashi. Narrow spectral linewidth operation (<160  kHz) in widely tunable distributed feedback laser array. IEEE Electron. Lett., 46, 714-715(2010).

[9] A. Kasukawa, T. Mukaihara. High power, narrow linewidth tunable lasers. OptoElectronics and Communication Conference and Australian Conference on Optical Fibre Technology, 965-966(2014).

[10] H. Ishii, F. Kano, Y. Tohmori, Y. Kondo, T. Tamamura, Y. Yoshikuni. Narrow spectral linewidth under wavelength tuning in thermally tunable super-structure-grating (SSG) DBR lasers. IEEE J. Sel. Top. Quantum Electron., 1, 401-407(1995).

[11] M. C. Larson. Narrow linewidth tunable DBR lasers. International Semiconductor Laser Conference, TuC2(2016).

[12] U. Eriksson, J. Wesström, Y. T. Liu, S. Hammerfeldt, M. Hassler, B. Stoltz, N. Carlsson, S. Siraj, E. Goobar, Y. Matsui. High performance narrow linewidth thermally tuned semiconductor laser. European Conference on Optical Communication, 1-3(2015).

[13] Y. Matsui, U. Eriksson, J. Wesstrom, Y. T. Liu, S. Hammerfeldt, M. Hassler, B. Stoltz, N. Carlsson, S. Siraj, E. Goobar. Narrow linewidth tunable semiconductor laser. Compound Semiconductor Week, 1-2(2016).

[14] C. Henry. Theory of the linewidth of semiconductor lasers. IEEE J. Quantum Electron., 18, 259-264(1982).

[15] S. C. Davies, N. D. Whitbread, A. J. Ward, M. Arnold, R. A. Griffin, M. J. Wale. Reduce Lorentzian linewidth for monolithic widely tunable C-band lasers utilizing InGaAlAs/InP active region. Lasers & Electro-optics Europe and 12th European Quantum Electronics Conference, CI3_3(2011).

[16] S. C. Davies, R. A. Griffin, A. J. Ward, N. D. Whitbread, I. Davies, L. Langley, S. Fourte, J. Mo, Y. Xu, A. Carter. Narrow linewidth, high power, high operating temperature digital supermode distributed Bragg reflector laser. 39th European Conference & Exhibition on Optical Communication, 1-3(2013).

[17] Q. A. Chen, C. Jiang, X. Ma, Y. Liu, D. T. Yang, Q. Y. Lu, W. H. Guo. 1 × 8 MMI based multi-channel interference laser integrated with SOA through a 2-port multimode interference reflector. Opt. Express, 26, 19940-19949(2018).

[18] Q. A. Chen, Q. Y. Lu, W. H. Guo. Theory and simulation of multi-channel interference (MCI) widely tunable lasers. Opt. Express, 23, 18040-18051(2015).

[19] Q. A. Chen, X. Ma, W. Sun, Y. Liu, G. H. Liu, G. Y. Zhao, Q. Y. Lu, W. H. Guo. Demonstration of multi-channel interference widely tunable semiconductor laser. IEEE Photon. Technol. Lett., 28, 2862-2865(2016).

[20] X. M. Han, Q. Cheng, F. Liu, Y. L. Yu. Numerical analysis on thermal tuning efficiency and thermal stress of a thermally tunable SG-DBR laser. IEEE Photon. J., 8, 1501512(2016).

[21] Q. A. Chen, G. H. Liu, Q. Y. Lu, W. H. Guo. Optimization algorithm based characterization scheme for tunable semiconductor lasers. Opt. Express, 24, 20982-20992(2016).

[22] T. N. Huynh, L. Nguyen, L. P. Barry. Phase noise characterization of SGDBR lasers using phase modulation detection method with delayed self-heterodyne measurements. IEEE J. Lightwave Technol., 31, 1300-1308(2013).

[23] L. B. Mercer. 1/f frequency noise effects on self-heterodyne linewidth measurements. IEEE J. Lightwave Technol., 9, 485-493(1991).

[24] W. H. Guo, D. C. Byrne, Q. Y. Lu, B. Corbett, J. F. Donegan. Fabry–Pérot laser characterization based on the amplified spontaneous emission spectrum and the fourier series expansion method. IEEE J. Sel. Top. Quantum Electron., 17, 1356-1363(2011).