Dhaka University Journal of Applied Science & Engineering

• Sazzad MS Imran
  Dept. of Electrical and Electronic Engineering, University of Dhaka, Bangladesh
• Razia Sultana
  Dept. of Electrical and Electronic Engineering, University of Dhaka, Bangladesh
• HM Asif Tanmay
  Dept. of Electrical and Electronic Engineering, University of Dhaka, Bangladesh
• Nahid Hassan
  Dept. of Electrical and Electronic Engineering, University of Brahmanbaria, Brahmanbaria-3400, Bangladesh

A theoretical investigation has been carried out for both the direct sinusoidal modulation and associated noise performance of InGaN based quantum well (QW) semiconductor laser diodes (LDs) operating in multimode. The study is based on the QW lasers with two separate quantum wells with different carrier injection ratios. A model of multimode rate equations is developed by taking into account both symmetric and asymmetric cross-gain saturation. Numerical simulation shows that the mode partition effect exists in both the modulated and unmodulated LDs. From modulation at microwave frequency, highly synchronized oscillation of the modes resulting periodic pulse-like output is observed that contains peaks at modulation frequency and its harmonics. Associated total RIN and modal RIN values suppress with the modulation index. The simulation results have well correspondence with the previously reported theoretical and experimental findings

1. L. Chen, “Quantum well lasers and their applications”, International Journal of High Speed Electronics and Systems, vol. 7, no. 3, pp. 373-381, 1996
2. B.R. Nag, “Physics of quantum well devices”, Solid-State Science and Technology Library, Kluwer Academic Publishers, Springer, 2000.
3. M. Ahmed and M. Yamada, “Influence of Instantaneous Mode Competition on the Dynamics of Semiconductor Lasers,” IEEE J. Quantum Electron., vol. 38, no. 6, pp. 682-693, 2002.
4. N. Ogasawara and R. Ito, “Longitudinal Mode Competition and Asymmetric Gain Saturation in Semiconductor InjectionLasers: I. Experiment,” Jpn. J. Appl. Phys., vol. 27, no. 4, pp. 607-614, 1988.
5. M. Yamada, W. Ishimori, H. Sakaguchi, and M. Ahmed, “Time-Dependent Measurement of the Mode-Competition Phenomena among Longitudinal Modes in Long-Wavelength Lasers,” IEEE J. Quantum Electron., vol. 39, no. 12, pp. 1548-1554, 2003.
6. M. Ahmed, “Numerical Characterization of Intensity and Frequency Fluctuations Associated with Mode Hopping and Single-Mode Jittering in Semiconductor Lasers,” Physica D., vol. 176, no. 3-4, pp. 212-236, 2003.
7. K.Y. Lau, C.M. Gee, T.R. Chen, N. Bar-Chaim, and I. Ury, “Signal-Induced Noise in Fiber-Optic Links using Directly Modulated Fabry-Perot and Distributed-Feedback Laser Diodes,” J. Lightwave Technol., vol. 11, no. 7, pp. 1216-1225, 1993.
8. M. Ahmed, S.W.Z. Mahmoud, and S.A. Mahmoud, “Study of the Optical Feedback-Induced Noise in Semiconductor Lasers and Applications to the Optic Disc System,” Phys. Wave Phenom., vol. 22, no. 1, pp. 61-68, 2014.
9. M. Ahmed and A. El-Lafi, “Large-Signal Analysis of Analog Intensity Modulation of Semiconductor Lasers,” Opt. Laser Technol., vol. 40, no. 6, 809, 2008.
10. M. Ahmed and M. Yamada, “Mode Oscillation and Harmonic Distortions Associated with Sinusoidal Modulation of Semiconductor Lasers,” Eur. Phys. J., vol. 66, issue 9, id 246, 2012.
11. M. Ahmed and M. Yamada, “Theoretical Analysis of Mode-Competition Noise in Modulated Laser Diodes and Its Influence on Noise Performance of Fiber Links,” J. Phys. D.: Applied Physics, vol. 45, no. 40, article id. 405102, 2012.
12. A. Bakry and M. Ahmed, “Influence of Sinusoidal Modulation on Mode Competition and Signal Distortion in Multimode InGaAsP Lasers,” Opt. Laser Technol., vol. 50, pp. 134-140, 2013
13. L. Uhlig, M. Wachs, D.J. Kunzmann, and U.T. Schwarz, “Spectral-temporal dynamics of (Al,In)GaN laser diodes”, Optics Express, vol. 28, no. 2, pp. 1771-1789, 2020.
14. W. Scheibenzuber, “GaN-based laser diodes: Towards longer wavelengths and short pulses,” PhD Thesis, Universität Freiburg, 2011.
15. W.G. Scheibenzuber and U.T. Schwarz, “Unequal pumping of quantum wells in GaN-based laser diodes,” Appl. Phys. Express, vol. 5, issue. 4, no. 2, article id. 042013, 2012.
16. M. Yamada, “Theoretical analysis of nonlinear optical phenomena taking into account the beating vibration of the electron density in semiconductor lasers,” J. Appl. Phys., vol. 66, no. 1, pp. 81-89, 1989.
17. G. Ropars, A. Le Floch, and G. Agrawal, “Spectral and spatial dynamics in InGaN blue-violet lasers,” Appl. Phys.Lett., vol. 89 243902, 2006.
18. M.H. Chen, S.C. Hsiao, K.T. Shen, C.C. Tsai, and H.C. Chui, “The spectral mode evolution in a blue InGaN laser diode,” Optik, vol. 186, pp. 41-45, 2019.
19. S.M.S. Imran, M. Yamada and Y. Kuwamura, “Theoretical analysis of the optical feedback noise based on multimode model of semiconductor lasers”, IEEE J. of Quantum Electron., vol. 48, issue 4, pp. 521-527, 2012.
20. T. Weig, T. Hager, G Buderl, U. Strauss, and U.T. Schwarz, “Longitudinal mode competition and mode clustering in (Al,In)GaN laser diodes,” Optics Express, vol. 22, no. 22, pp. 27489-27503, 2014.
21. H. Ishikawa, M. Yano, and M. Takusagawa, “Mechanism of Asymmetric Longitudinal Mode Competition in InGaAsP/InP Lasers,” Appl. Phys. Lett., vol. 40, pp. 553-555, 1982.
22. A. Bakry and M. Ahmed, “Multimode analysis of relative intensity noise associated with intensity modulation of semiconductor lasers”, Journal of Modern Optics, vol. 22, no. 2, pp. 103-110, 2014.
23. M. Ahmed, “Longitudinal Mode Competition in Semiconductor Lasers under Optical Feedback: Regime of Short-External Cavity,” Opt. Laser Technol., vol. 41, no. 1, pp. 53-63, 2009.
24. M. Yamada, “Transverse and Longitudinal Mode Control in Semiconductor Injection Lasers,” IEEE. J. Quantum Electron., vol. QE-19, pp. 817-882, 1983.
25. T.B. Anderson and B.R. Clarke, “Modeling Mode Partition Noise in Nearly Single-Mode Intensity Modulated Lasers,” IEEE J. Quantum Electron., vol. 29, no. 1, pp. 3-13, 1993.
26. G.L. Abbas and T.K. Yee, “Power Dropout Statistics of Nearly-Single-Longitudinal-Mode Semiconductor Lasers,” IEEE J. Quantum Electron., vol. 21, no. 9, pp. 1303-1307, 1985.
27. G. Gray and R. Roy, “Noise in Nearly-Single-Mode Semiconductor Lasers,” Phys. Rev. A., vol. 40, no. 5, pp. 2452-2462, 1989.
28. M. Ohtsu, Y. Otsuka, and Y. Teramachi, “Analyses of Mode Partition and Mode Hopping in Semiconductor Lasers,” IEEE J. Quantum Electron., vol. 25, no.1, pp. 31-38, 1989.
29. M. Ahmed, A. El-Lafi, “Analysis of small-signal intensity modulation of semiconductor lasers taking account of gain suppression”, Pramana - J Phys, vol. 71, pp. 99-115, 2008.
30. C.H. Lee, T.H. Yoon and S.Y. Shin, “Period doubling and chaos in a directly modulated laser diode”, Appl. Phys. Lett., vol. 46, no. 1, pp. 95-97, 1985.