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arXiv · 1104.1170

Quantum entanglement of a tunneling spin with mechanical modes of a torsional resonator

D. A. Garanin·E. M. Chudnovsky
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Abstract

We solve Schrödinger equation describing a tunneling macrospin coupled to a torsional oscillator. Energy spectrum is studied for various quantum regimes. Magnetic susceptibility and noise spectrum are computed. We show that entanglement of the spin with mechanical modes of a subnanometer oscillator results in the decoherence of spin tunneling. For larger oscillators the presence of a tunneling spin can be detected through splitting of the mechanical mode at the resonance. Our results apply to experiments with magnetic molecules coupled to nanoresonators.

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D. A. Garanin, E. M. Chudnovsky. 2011-04-06. Quantum entanglement of a tunneling spin with mechanical modes of a torsional resonator. https://doi.org/10.1103/physrevx.1.011005

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