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arXiv · 1006.5144

Multitudes of Stable States in a Periodically Driven Electron-Nuclear Spin System in a Quantum Dot

V. L. Korenev
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Abstract

The periodical modulation of circularly polarized light with a frequency close to the electron spin resonance frequency induces a sharp change of the single electron spin orientation. Hyperfine interaction provides a feedback, thus fixing the precession frequency of the electron spin in the external and the Overhauser field near the modulation frequency. The nuclear polarization is bidirectional and the electron-nuclear spin system (ENSS) possesses a few stable states. A similar frequency-locking effect exists for two-color and mode-locked excitations, too. However, the pulsed excitation with mode locked laser brings about the multitudes of stable states in ENSS in a quantum dot. The resulting precession frequencies of the electron spin differ in these states by the multiple of the modulation frequency. Under such conditions ENSS represents a digital frequency converter with more than a hundred stable channels.

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V. L. Korenev. 2011-03-21. Multitudes of Stable States in a Periodically Driven Electron-Nuclear Spin System in a Quantum Dot. https://doi.org/10.1103/physrevb.83.235429

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