Author(s): Ning, C (Ning, Chao); Sun, RX (Sun, Rui-Xuan); Liu, SM (Liu, Shu-Man); Zhang, JC (Zhang, Jin-Chuan); Zhuo, N (Zhuo, Ning); Liu, JQ (Liu, Jun-Qi); Wang, LJ (Wang, Li-Jun); Zhai, SQ (Zhai, Shen-Qiang); Liu, FQ (Liu, Feng-Qi); Wang, ZG (Wang, Zahn-Guo)

Source: OPTICS EXPRESS Volume: 30 Issue: 16 Pages: 29007-29014 DOI: 10.1364/OE.465716 Published: AUG 1 2022

Abstract: A second-order distributed feedback interband cascade laser emitting at 3.25 mu m was designed, grown, and fabricated. By coherent epitaxy of a GaSb cap layer instead of the conventional thin InAs cap on top of the laser structure, a high-quality surface grating was made of GaSb and gold. Enough coupling strength and a significant inter-modal loss difference were predicted according to the simulation within the framework of couple-wave theory. Lasers having 2-mm-long cavities and 4.5-mu m-wide ridges with high-/anti-reflection coatings were fabricated. The continuous-wave threshold current and maximum single-mode output power were 60 mA and 24 mW at 20 degrees C, respectively. The output power of 5 mW was still kept at 55 degrees C. Continuous tuning free from mode hopping and high single-mode suppression ratios (>20dB) were realized at all injection currents and heat-sink temperatures, covering a spectral range of over 20 cm(-1). (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Accession Number: WOS:000836698500062

ISSN: 1094-4087

Full Text: https://opg.optica.org/oe/fulltext.cfm?uri=oe-30-16-29007&id=481188