High-power, wide-temperature-range operation of InGaAsP/InP strained-layer MQW lasers with a reverse-mesa ridge-waveguide structure

Abstract

Low-cost, long-wavelength laser diodes that operate reliably without temperature control over a wide temperature range (WTR) are key components in fiber-in-the-loop applications rapidly being developed. InP-based ridge-waveguide (RWG) lasers have recently been reported to have a high potential for practical use because of their simple fabrication with high process uniformities,1,2 high WTR performance,2–4 low parasitics,2,4,5 and high reliability.2,4 Most of these lasers use a rectangular ridge with vertical sidewalls formed by conventional wet etching. In this paper we propose a reverse-mesa (RM) RWG laser structure that further improves long-wavelength RWG laser performance. Direct comparison between the RM-RWG lasers and conventional vertical-mesa (VM) RWG lasers clearly reveals substantial reductions in threshold currents, series resistance, and waveguide loss for the proposed structure.