From Dirac to Diffusion: Decoherence in Quantum Lattice Gases
Abstract
We describe a model for the interaction of the internal (spin) degree of freedom of a quantum lattice-gas particle with an environmental bath. We impose the constraints that the particle-bath interaction be fixed, while the state of the bath is random, and that the effect of the particle-bath interaction be parity invariant. The condition of parity invariance defines a subgroup of the unitary group of actions on the spin degree of freedom and the bath. We derive a general constraint on the Lie algebra of the unitary group which defines this subgroup, and hence guarantees parity invariance of the particle-bath interaction. We show that generalizing the quantum lattice gas in this way produces a model having both classical and quantum discrete random walks as different limits. We present preliminary simulation results illustrating the intermediate behavior in the presence of weak quantum noise.
Cite
@article{arxiv.quant-ph/0507022,
title = {From Dirac to Diffusion: Decoherence in Quantum Lattice Gases},
author = {Peter J. Love and Bruce M. Boghosian},
journal= {arXiv preprint arXiv:quant-ph/0507022},
year = {2007}
}
Comments
To appear in QIP