Nonlinear optical properties of semiconductor quantum wires

摘要

Abstract: Nonlinear optical absorption at discrete frequencies has been observed in semiconductor quantum wires crystallized in transparent dielectric matrix (inside chrysotile asbestos nanotubes). The induced changes of absorption in quantum wires have been explained by phase space filling, quantum- confined Stark effect and screening of excitons; filling of the size-quantized energy bands with nonequilibrium carriers (dynamic Burstein-Moss effect); renormalization of the 1D energy bands at high density of the induced plasma. The measured values of exciton binding energies are much greater than that of the corresponding bulk semiconductors. The increase of the exciton binding energy may be attributed not only to the quantum confinement but also to the `dielectric confinement' - to the increase of electron-hole attraction because of the difference in dielectric constants of semiconductor nanowires and dielectric matrix.!20