The effect of classical noise on a quantum two-level system
نویسندگان
چکیده
We consider a quantum two-level system perturbed by classical noise. The noise is implemented as a stationary diffusion process in the off-diagonal matrix elements of the Hamiltonian, representing a transverse magnetic field. We determine the invariant measure of the system and prove its uniqueness. In the case of Ornstein–Uhlenbeck noise, we determine the speed of convergence to the invariant measure. Finally, we determine an approximate one-dimensional diffusion equation for the transition probabilities. The proofs use both spectral-theoretic and probabilistic methods. Date. May 7, 2008. 2000 Mathematical Subject Classification. 60h10, 35P15 (primary), 81Q15, 93E03 (secondary)
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