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Tunneling with dissipation and decoherence for a large spin

E. M. Chudnovsky·X. Martinez-Hidalgo
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Abstract

We present rigorous solution of problems of tunneling with dissipation and decoherence for a spin of an atom or a molecule in an isotropic solid matrix. Our approach is based upon switching to a rotating coordinate system coupled to the local crystal field. We show that the spin of a molecule can be used in a qubit only if the molecule is strongly coupled with its atomic environment. This condition is a consequence of the conservation of the total angular momentum (spin + matrix), that has been largely ignored in previous studies of spin tunneling.

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E. M. Chudnovsky, X. Martinez-Hidalgo. 2002-02-18. Tunneling with dissipation and decoherence for a large spin. https://doi.org/10.1103/physrevb.66.054412

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