Open AccessCarrier spin relaxation in (Ga,Mn)As at room temperature
Author(s) -
刘晓东,
王玮竹,
高瑞鑫,
赵建华,
文锦辉,
林位株,
赖天树
Publication year - 2008
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.57.3857
Subject(s) - materials science , relaxation (psychology) , excitation , condensed matter physics , femtosecond , ferromagnetism , kerr effect , electron , ultrashort pulse , spectroscopy , spin (aerodynamics) , exchange interaction , atomic physics , laser , physics , optics , thermodynamics , psychology , social psychology , quantum mechanics , nonlinear system
In this paper, the excitation energy density dependence of carrier spin relaxation is studied at room temperature for the as-grown and annealed (Ga,Mn)As samples using femtosecond time-resolved pump-probe Kerr spectroscopy. It is found that spin relaxation lifetime of electrons lengthens with increasing excitation energy density for both samples, and the annealed (Ga,Mn)As has shorter carrier recombination and electron spin relaxation lifetimes as well as larger Kerr rotation angle than the as-grown (Ga,Mn)As under the same excitation condition, which shows that DP mechanism is dominant in the spin relaxation process for (Ga,Mn)As at room temperature. The enhanced ultrafast Kerr effect in the annealed (Ga,Mn)As shows the potential application of the annealed (Ga,Mn)As in ultrafast all-optical spin switches, and also provides a further evidence for the p-d exchange mechanism of the ferromagnetic origin of (Ga,Mn)As.