Optical properties of InP/GaInP quantum-dot laser structures

摘要

We have grown InP quantum dots with different rates and on substrates with different orientations. The growth conditions have a major influence on the form of the gain spectrum. Using a high growth rate on a 10degrees off (100) substrate we obtain a broad gain spectrum due to contributions from a bimodal dot size distribution whereas a sample containing mostly small dots, produced using (211)B substrates, has a narrower gain spectrum centered at a shorter wavelength of similar to700-710 nm. The modal gain saturates at a magnitude significantly smaller than the modal absorption, nevertheless the measured values of modal gain are sufficient to sustain laser action, and structures grown at high growth rate on 10degrees off (100) substrates are capable of providing laser devices operating in the region of 750 nm. (C) 2004 American Institute of Physics.