Evaluation of Decoherence for Quantum Computing Architectures: Qubit System Subject to Time-Dependent Control
Abstract
We present an approach that allows quantifying decoherence processes in an open quantum system subject to external time-dependent control. Interactions with the environment are modeled by a standard bosonic heat bath. We develop two unitarity-preserving approximation schemes to calculate the reduced density matrix. One of the approximations relies on a short-time factorization of the evolution operator, while the other utilizes expansion in terms of the system-bath coupling strength. Applications are reported for two illustrative systems: an exactly solvable adiabatic model, and a model of a rotating-wave quantumcomputing gate function. The approximations are found to produce consistent results at short and intermediate times.
Cite
@article{arxiv.cond-mat/0506286,
title = {Evaluation of Decoherence for Quantum Computing Architectures: Qubit System Subject to Time-Dependent Control},
author = {Dmitry Solenov and Vladimir Privman},
journal= {arXiv preprint arXiv:cond-mat/0506286},
year = {2010}
}
Comments
26 pages in PDF, 6 figures, 1 table; Typos corrected