Dual-Wavelength Y-Branch DBR Lasers With 100 mW of CW Power Near 2 μm

• Published in: IEEE photonics technology letters 2020-09, Vol.32 (17), p.1017-1020
• Main Authors: Jiang, Jiang, Shterengas, Leon, Stein, Aaron, Kipshidze, Gela, Belyanin, Alexey, Belenky, Gregory
• Format: Article
• Language: English
• Subjects: Continuous radiation; DBR; DBR lasers; Distributed Bragg reflectors; Etching; GaSb-based; Lasers; Measurement by laser beam; Mid-infrared; NANOSCIENCE AND NANOTECHNOLOGY; Power lasers; Quantum wells; Semiconductor lasers; Surface emitting lasers; type-I quantum well; Waveguide lasers; Waveguides; Y-branch
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2020.3009663

The interband GaSb-based diode lasers emitting simultaneously in two narrow bands separated by either ~1.6 or ~3.3 THz were designed, fabricated and characterized. The device active region contained one asymmetric tunnel-coupled double quantum well with separation between two lowest electron subbands controlled by thickness of the tunnel barrier. The Y-branch 6 th order distributed Bragg reflector devices have been fabricated with either deep or shallow etched ridge waveguides. The increase of the deeply etched ridge waveguide width from 10 to 20~\mu \text{m} improved laser threshold and efficiency thanks to reduction of the relative role of the sidewall defect recombination. Further improvement of the device performance parameter was achieved by shallow etching. The shallow etched lasers with stable dual-wavelength emission spectrum generated 100 mW of continuous wave output power at 20 °C.