Design of a 1654 nm InP-Based VCSEL with a Single-Layer MHCG Top Output-Coupling Mirror

Conventional long-wavelength vertical-cavity surface-emitting lasers (VCSELs) require thick distributed Bragg reflectors (DBRs) to provide high-reflectance optical feedback. We present a numerical design of a 1654 nm InP-based VCSEL with a single-layer monolithic high-contrast grating (MHCG) top output-coupling mirror. The optimized mirror achieves a zero-order reflectance of 99.29% for transverse-electric (TE) polarization near 1654 nm. Complete-cavity simulations show a longitudinal standing wave overlapping the quantum wells. At 5 mA, the MHCG architecture reduces whole-device Joule power by 91.53% relative to the DBR reference. A matched active-core heat load gives a 23.94% higher active-to-sink thermal resistance for MHCG, separating resistive heat reduction from heat-extraction performance. The design combines axial optical feedback with reduced top-reflector thickness and lower Joule heating, providing a basis for optical and thermal-path co-design.