The lateral coupling effect in InAs/InGaAsP/InP quantum dash

Abstract

In this study, we investigate the lateral tunneling coupling of InAs/InGaAsP quantum dash (Qdash) and its influence on the optical and carrier transport properties. The band structure and optical transmission energy of isolated Qdashes and the effects of lateral interdash coupling are explored by the eight-band k ⋅ p model. The impact of these tunneling effects on the carrier dynamics is further examined through simulations of laser performance using a time-domain traveling-wave model. The results show that tunneling coupling can reduce the threshold current in large-volume devices but have a limited effect on small-volume vertical cavity surface emitting lasers. This study provides valuable insights into the morphological control of Qdash materials for optimizing laser performance, with particular attention to the role of tunneling in enhancing carrier transport efficiency.