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Single electron Transport in diluted magnetic semiconductor quantum dots. J. Fernández-Rossier, R. Aguado. Department of Applied Physics, U. Alicante SPAIN Material Science Institute of Madrid, CSIC SPAIN. CdTe+1 Mn. Gate Tuning Anisotropy. Spin dependent Capacitance.
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Single electron Transport in diluted magnetic semiconductor quantum dots J. Fernández-Rossier, R. Aguado Department of Applied Physics, U. Alicante SPAIN Material Science Institute of Madrid, CSIC SPAIN CdTe+1 Mn Gate Tuning Anisotropy Spin dependent Capacitance www.ua.es/personal/jfrossier/ Z19-1
GaMnAs Single electron transistor cond-mat/0602608 Coulomb blockade anisotropic magnetoresistance: Single electronics meets spintronicsAuthors:J. Wunderlich et al.
Y. Léger et al., PRL 95, 047403 (05) L. Besombes et al. PRL93, 207403(04) Single ExcitonSpectroscopy Mn(2+) S=5/2 2S+1=6 PL Intensity 1 Mn per dot www.ua.es/personal/jfrossier/
Heisenberg ST=Se+M Mz Ising
Single exciton spectroscopy (1 Mn dot) EXPERIMENTS: Y. Léger et al. PRL 95, 047403 (05) WE UNDERSTAND e+h+Mn THEORY: J. Fernández-Rossier,PRB73, 045301 (06)
Theory I: The dot STATES NUMERICAL DIAGONALIZATION STATES WITH a FIXED NUMBER of CARRIERS (Controlled By Gate Voltage)
GATE CONTROL of Magnetic Anisotropy ST Mz Ising Heisenberg ZXX Free HH LH Q=-1 Q=0 Q=+1 Q=+3
Theory: Single electron transport Density matrix (Vg, Vb) MASTER EQUATION Scattering Rates
CHARGING the dot E Q=2 Q=1 Q=0 VG Q G Q=2 Q=1 Q=0 VG
CHARGING the dot Spin dependent CHARGING ENERGY 3 PEAKS instead of 1 !! S=2 S=3
E VG
E VG
E VG
E Q=0 VG
E Q=1/3 VG
E Q=2/3 VG
E Q=3/3 VG
CONCLUSIONS Electric Tuning of magnetic anisotropy SPINconditional charging energy Q=+1 Q=+3 Mz Ising ZXX www.ua.es/personal/jfrossier/