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Title: Laterally coupled distributed feedback type-I quantum well cascade diode lasers emitting near 3.22 μm

The laterally coupled distributed feedback (LC-DFB) GaSb-based type-I quantum well cascade diode lasers using the second- and the sixth-order gratings to stabilize the output spectrum near 3.22 μm were designed and fabricated in this paper. The laser heterostructure contained three cascades. The devices were manufactured using a single dry etching step defining the ~5-μm-wide ridge with ~5-μm-wide gratings sections adjacent to the ridge sides. The grating coupling coefficients were estimated to be about 1 cm -1. The stability of the single-frequency operation was ensured by alignment of the DFB mode to the relatively wide gain peak. The 2-mm-long second-order LC-DFB lasers generated above 10 mW of continuous-wave (CW) output power at 20°C in epi-side-up configuration and demonstrated power conversion efficiency above 2%. The sixth-order LC-DFB lasers showed lower efficiency but still generated several milliwatts of CW output power. Finally, the devices demonstrated a CW current tuning range of about 3.5 nm at the temperature of 20°C.
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  1. Stony Brook Univ., NY (United States). Electrical and Computer Engineering
  2. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 1559-128X
Grant/Contract Number:
SC0012704; ECCS-1408126; W911NF1110109
Accepted Manuscript
Journal Name:
Applied Optics
Additional Journal Information:
Journal Volume: 56; Journal Issue: 31; Journal ID: ISSN 1559-128X
Optical Society of America
Research Org:
Stony Brook Univ., NY (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF); US Army Research Office (ARO); China Scholarship Council (CSC)
Country of Publication:
United States
36 MATERIALS SCIENCE; infrared and far-infrared lasers; semiconductor lasers; distributed-feedback lasers
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1399819