Spin Environment Engineering for a Persistent Current Qubit
Condensed Matter
2007-05-23 v1 Quantum Physics
Abstract
A persistent current qubit has two quantum states with opposite currents flowing in a superconducting loop. Their magnetic field couple to nuclear spins. The qubit state is not only perturbed by the spins but it also gets entangled with the spins' state on a very short timescale. However, when the same spins are exposed to a strong but less than critical external magnetic field, then the qubit field is just a small perturbation on top of the external field and the entanglement with each spin is negligible. For a qubit which is more microscopic than certain threshold this partial entanglement results in negligible partial decoherence.
Cite
@article{arxiv.cond-mat/0101454,
title = {Spin Environment Engineering for a Persistent Current Qubit},
author = {Jacek Dziarmaga},
journal= {arXiv preprint arXiv:cond-mat/0101454},
year = {2007}
}
Comments
4 pages in RevTex plus 2 .eps figures