Ultrafast time-resolved quantum beats in the polarization state of coherent emission from quantum wells

摘要

Dual-channel spectral interferometry is used to measure the ellipticity, the orientation of the polarization ellipse, and the sense of rotation of the four-wave-mixing signal from a GaAs-AlGaAs multiple quantum well. Each parameter is observed to oscillate dramatically at the heavy-hole-light-hole quantum heat frequency. During each beat period (in the strong quantum beat regime), the ellipticity oscillates twice between linear and almost-circular polarization, the orientation of the polarization ellipse rotates through a complete 180 degrees, and the sense of rotation changes from left- to right-circular polarization. (C) 1998 Optical Society of America. [References: 13]