Low Threshold and High Speed Operation of 1.55-μm-Band Lasers by InP-Based Membrane Structure

Abstract

An overview of researches on semiconductor membrane lasers is presented. The membrane structure, which consists of very thin III-V core layers sandwiched by low index dielectric or air claddings, can enhance optical confinement to the III-V layers. This enhancement enables very low threshold current and highly efficient laser operation. An on-chip optical interconnection is one of the applications for membrane photonic integrated circuits toward large scale data center computing. Such application will require over 0.16 mW output power and 10 Gbit/s modulation with an operating current less than 1 mA. In theoretical calculations, these requirements can be met by membrane laser structures. In actual devices, a threshold current of 250 μA was achieved and a modulation efficiency of 9.9 GHz/ mA was demonstrated with InP-based membrane structure on Si substrate.