Infrared probe of the insulator-to-metal transition in Ga1-xMnxAs and Ga1-xBexAs

被引:26
作者
Chapler, B. C. [1 ]
Myers, R. C. [2 ]
Mack, S. [3 ]
Frenzel, A. [1 ]
Pursley, B. C. [1 ]
Burch, K. S. [4 ,5 ]
Singley, E. J. [6 ]
Dattelbaum, A. M. [7 ]
Samarth, N. [8 ]
Awschalom, D. D. [3 ]
Basov, D. N. [1 ]
机构
[1] Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA
[2] Ohio State Univ, Dept Mat Sci & Engn, Columbus, OH 43210 USA
[3] Univ Calif Santa Barbara, Ctr Spintron & Quantum Computat, Santa Barbara, CA 93106 USA
[4] Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada
[5] Univ Toronto, Inst Opt Sci, Toronto, ON M5S 1A7, Canada
[6] Calif State Univ E Bay, Dept Phys, Hayward, CA 94542 USA
[7] Los Alamos Natl Lab, Los Alamos, NM 87545 USA
[8] Penn State Univ, Dept Phys, University Pk, PA 16802 USA
来源
PHYSICAL REVIEW B | 2011年 / 84卷 / 08期
基金
美国国家科学基金会;
关键词
MAGNETIC SEMICONDUCTORS; FERROMAGNETISM; TEMPERATURE; SPECTRA; BAND;
D O I
10.1103/PhysRevB.84.081203
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We report infrared studies of the insulator-to-metal transition (IMT) in GaAs doped with either magnetic (Mn) or nonmagnetic acceptors (Be). We observe a resonance with a natural assignment to impurity states in the insulating regime of Ga1-xMnxAs, which persists across the IMT to the highest doping (16%). Beyond the IMT boundary, behavior combining insulating and metallic trends also persists to the highest Mn doping. Be-doped samples, however, display conventional metallicity just above the critical IMT concentration, with features indicative of transport within the host valence band.
引用
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页数:4
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