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】

Free