Frequency Comb Generation at 800 nm in Waveguide Array Quantum Well Diode Lasers

• Published in: IEEE journal of quantum electronics Vol. 56; no. 1; pp. 1 - 9
• Main Authors: Sun, Chang, Dong, Mark, Mangan, Niall M., Winful, Herbert G., Cundiff, Steven T., Kutz, J. Nathan
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.02.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Computer simulation; Coupling coefficients; Diode lasers; Laser applications; Laser arrays; Laser mode locking; Mathematical model; Mathematical models; optical frequency combs; Optical waveguides; Quantum wells; Robustness (mathematics); Semiconductor device modeling; Semiconductor diodes; Semiconductor lasers; Traveling waves; Waveforms; waveguide arrays; Waveguide lasers; Waveguides
• ISSN: 0018-9197; 1558-1713
• DOI: 10.1109/JQE.2019.2960133

A traveling wave model for a semiconductor diode laser based on quantum wells is presented as well as a comprehensive theoretical model of the lasing dynamics produced by the intensity discrimination and controllable loss of mode-coupling in a waveguide array. By leveraging a recently developed model for the detailed semiconductor gain dynamics, the temporal shaping effects of the nonlinear mode-coupling induced by the waveguide arrays can be characterized. Specifically, the enhanced pulse shaping and loss provided by the waveguides is capable of generating stable frequency combs at a wavelength of 800 nm in a GaAs device, a parameter regime for which it is difficult to obtain stable, broad comb generation using a single waveguide. Extensive numerical simulations showed that stable waveform generation could be achieved and optimized by an appropriate choice of the linear waveguide coupling coefficient, quantum well depth, and the input currents to the first and second waveguides. The model provides a demonstration that a compact, efficient and robust on-chip comb source can be produced in GaAs.