Carrier diffusion effect in tapered semiconductor-laser amplifier

• Published in: IEEE journal of quantum electronics Vol. 34; no. 7; pp. 1247 - 1256
• Main Authors: LAI, J.-W, LIN, C.-F
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-07-1998; Institute of Electrical and Electronics Engineers
• Subjects: Exact sciences and technology; Fluctuations; Fundamental areas of phenomenology (including applications); High power amplifiers; Laser beams; Laser optical systems: design and operation; Optical beams; Optical distortion; Optics; Physics; Power amplifiers; Power generation; Pulse amplifiers; Resonators, cavities, amplifiers, arrays, and rings; Semiconductor lasers; Semiconductor optical amplifiers; Semiconductor lasers; Radiation quality; Charge carrier scattering; Quantum wells; Theoretical study; Optical amplifier; Diffusion coefficient; Heterostructures
• ISSN: 0018-9197; 1558-1713
• DOI: 10.1109/3.687869

This paper proposes a theoretical model to study the beam amplification and the influence of the lateral drift and diffusion on the tapered semiconductor-laser amplifier in great detail. The overall effect of the lateral drift and diffusion could be represented by an effective diffusion coefficient. The analysis, which treats the effective diffusion coefficient as a controllable parameter, shows that both the beam quality and optoelectrical property can be improved using a large effective diffusion coefficient. The analysis also indicates that the effective diffusion in the separate-confinement heterostructure layer could affect the beam quality in the quantum-well amplifiers. In addition, the thermal effect on the device performance is studied and its influence is found to be extremely significant for the high-diffusion cases.