Abstract
Atomic force microscopy (AFM) and power-dependentmicro-photoluminescence (μ-PL) spectroscopy are used to study thestructure and exciton energy states in InAs quantum dots (QDs) grown onan In0.35Ga0.65As template on GaAs (311)B. TheIn0.35Ga0.65As template, consisting of a two-dimensionallymodulated layer of closely packed connected cells, has a remarkableeffect on the optical properties of the InAs QDs. By comparing theemission spectra of the samples without and with InAs QDs and the workcarried out by Gong et al. [J. Cryst. Growth 251 (2003) 150;Appl. Phys. Lett. 81 (2002) 3254] we conclude that the existence of theIn0.35Ga0.65As template enhances the photo-absorption andtherefore the exciton emission from the QDs due to efficient excitontransfer from the template into the QDs. Furthermore, the PL emissionfrom the QDs clearly reveals four discrete energy levels, S, P,D, and F with increasing excitation power.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
