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We report an investigation of V-coupled cavity interband cascade (IC) lasers (ICLs) emitting in the 3-μm wavelength range, employing various waveguide structures and coupler sizes. Type-II ICL devices with double-ridge waveguides exhibited wide tuning ranges exceeding 153 nm. Type-I ICL devices with deep-etched waveguides achieved single-mode emission with wavelength tunable over 100 nm at relatively high temperatures up to 250 K. All devices exhibited a side-mode suppression ratio higher than 30 dB. By comparing the performance of all devices with different sizes and configurations, a good tolerance against the structural parameter variations of the V-coupled cavity laser (VCCL) design is demonstrated, validating the advantages of the VCCL to achieve single-mode emission with wide tunability.
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Examination of the Durability of Interband Cascade Lasers Against Structural Variations
By studying two interband cascade laser (ICL) wafers with structural parameters that deviated considerably from the design, the durability of the device performance against structural variations was explored. Even with the lasing wavelength blue shifted by more than 700 nm from the designed value near 4.6 μm at 300 K, the ICLs still performed very well with a threshold current density as low as 320 A/cm2 at 300 K, providing solid experimental evidence of the tolerance of ICL performance on structural variations.
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- Award ID(s):
- 1931193
- PAR ID:
- 10179798
- Date Published:
- Journal Name:
- Hongwai yu haomibo xuebao
- Volume:
- 39
- Issue:
- 2
- ISSN:
- 1001-9014
- Page Range / eLocation ID:
- 137-141
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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