화학공학소재연구정보센터
Current Applied Physics, Vol.17, No.1, 31-36, 2017
Temperature behavior of Franz-Keldysh oscillation and evaluation of interface electric fields attributed to strain effect of InAs/GaAs quantum dot
In this work, the electric field-induced Franz-Keldysh effect was used to investigate the localized electric fields in GaAs interfaces attributed to strain effect of InAs/GaAs quantum dots (QD). The electric fields were investigated by photoreflectance spectroscopy (PR). PR spectra of the InAs/GaAs QDs showed complex Franz-Keldysh oscillations (FKOs) with various temperatures. It is suggested that the FKOs originated from the interface electric fields predominately caused by the strain-induced polarization at GaAs interface near the InAs QDs. The InAs/GaAs QDs have a broad range of interface electric fields from similar to 10(4) V/cm to similar to 2x10(5) V/cm. Temperature behavior of FKO amplitude distribution is explained by temperature dependent carrier confinement effect. (C) 2016 Elsevier B. V. All rights reserved.