EXCITON-HOLE COLLISION IN STAGGERED TYPE-II AL0.34GA0.66AS/ALAS MULTIPLE QUANTUM-WELLS | |
Article | |
关键词: GAAS/ALAS SUPERLATTICES; PHOTON-ECHOES; GAAS; TRANSITIONS; RELAXATION; LIGHT; | |
DOI : 10.1103/PhysRevB.44.5664 | |
来源: SCIE |
【 摘 要 】
We report the phase relaxation of GAMMA-GAMMA direct excitons in staggered type-II Al0.34Ga0.66As/AlAs multiple quantum wells by means of the time-resolved degenerate four-wave mixing. The dephasing rate increases with the increase in the excitation density. Its excitation density dependence sharply changes at a critical density of 0.2-mu-J/cm2. The dependence agrees with the excitation density dependence of the long-lived GAMMA-hole density studied by means of the pump-and-probe experiment. The long-lived hole density saturates at the same excitation density of 0.2-mu-J/cm2. These facts definitely indicate that the phase relaxation rate of GAMMA-GAMMA excitons is dominated by the collision between the excitons and long-lived holes.
【 授权许可】
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