Raman Scattering of InAs Quantum Dots with Different Deposition Thicknesses
不同淀积厚度InAs量子点的喇曼散射

The Raman scattering of InAs/GaAs self-assembled quantum dots(QDs) with different InAs thicknesses is investigated.The vibrational mode,which can be assigned to QD phonons,is observed.Analysis indicates that strain is the most important factor that influences the InAs QD frequency.As the InAs deposition thickness L increases,the InAs-like LO mode frequency decreases,which we attribute to the relaxation of the strain in the QD layer.In another sample with an InAlAs strain buffer layer,the AlAs-like LO mode shows a blue shift as L increases.This also supports the proposed strain relaxation process in QDs.