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تسجيل مستخدم جديدManipulation of the Spin Memory of Electrons in n-GaAs
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R. I. Dzhioev
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We report on the optical manipulation of the electron spin relaxation time in a GaAs based heterostructure. Experimental and theoretical study shows that the average electron spin relaxes through hyperfine interaction with the lattice nuclei, and that the rate can be controlled by the electron-electron interactions. This time has been changed from 300 ns down to 5 ns by variation of the laser frequency. This modification originates in the optically induced depletion of n-GaAs layer.
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We observe millisecond spin-flip relaxation times of donor-bound electrons in high-purity n-GaAs . This is three orders of magnitude larger than previously reported lifetimes in n-GaAs . Spin-flip times are measured as a function of magnetic field an
d exhibit a strong power-law dependence for fields greater than 4 T . This result is in qualitative agreement with previously reported theory and measurements of electrons in quantum dots.
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In a recent publication, Pfeffer and Zawadzki [cond-mat/0607150; Phys. Rev. B 74, 115309 (2006)] attempted a calculation of electron g factor in III-V heterostructures. The authors emphasize that their outcome is in strong discrepancy with our origin
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