A new local invariant for quantum gates
量子物理
2007-05-23 v1
摘要
In this paper we study the properties of two-qubit gates. We review the most common parameterizations for the local equivalence classes of two-qubit gates and the connections between them. We then introduce a new discrete local invariant, namely the number of local degrees of freedom that a gate can bind. The value of this invariant is calculated analytically for all the local equivalence classes of two-qubit gates. We find that almost all two-qubit gates can bind the full six local degrees of freedom and are in this sense more effective than the controlled-NOT gate, which only can bind four local degrees of freedom.
引用
@article{arxiv.quant-ph/0503141,
title = {A new local invariant for quantum gates},
author = {Laura Koponen and Ville Bergholm and Martti M. Salomaa},
journal= {arXiv preprint arXiv:quant-ph/0503141},
year = {2007}
}
备注
8 pages, 2 figures