Dissipation and Decoherence in a Quantum Register
Abstract
A model for a quantum register made of replicas of a -dimensional quantum system (cell) coupled with the environment, is studied by means of a Born-Markov Master Equation (ME). Dissipation and decoherence are discussed in various cases in which a sub-decoherent enconding can be rigorously found. For the qubit case () we have solved, for small the ME by numerical direct integration and studied, as a function of the coherence length of the bath, fidelity and decoherence rates of states of the register. For large enough the singlet states of the global pseudo-spin algebra of the register (noiseless at ) are shown to have a much smaller decoherence rates than the rest of the Hilbert space.
Cite
@article{arxiv.quant-ph/9705045,
title = {Dissipation and Decoherence in a Quantum Register},
author = {Paolo Zanardi},
journal= {arXiv preprint arXiv:quant-ph/9705045},
year = {2011}
}
Comments
minor corrections, references added, to appear in PRA (10 pages + 5 figures LaTeX)