2004/12/31 by Serguei Vorojtsov, Eduardo R. Mucciolo, Harold U. Baranger
Physics and Astronomy · #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.71.205322
published as Phys. Rev. B 71, 205322 (2005) (7 pages) · RevTex, 7 pages, 5 figures. v2: appendix added, more details provided. Accepted for publication in PRB
arxiv created 2005/05/03 · arxiv updated 2009/12/01
We study decoherence of a quantum dot charge qubit due to coupling to piezoelectric acoustic phonons in the Born-Markov approximation. After including appropriate form factors, we find that phonon decoherence rates are one to two orders of magnitude weaker than was previously predicted. We calculate the dependence of the Q-factor on lattice temperature, quantum dot size, and interdot coupling. Our results suggest that mechanisms other than phonon decoherence play a more significant role in current experimental setups.