Two-Bit Gates are Universal for Quantum Computation
摘要
A proof is given, which relies on the commutator algebra of the unitary Lie groups, that quantum gates operating on just two bits at a time are sufficient to construct a general quantum circuit. The best previous result had shown the universality of three-bit gates, by analogy to the universality of the Toffoli three-bit gate of classical reversible computing. Two-bit quantum gates may be implemented by magnetic resonance operations applied to a pair of electronic or nuclear spins. A ``gearbox quantum computer'' proposed here, based on the principles of atomic force microscopy, would permit the operation of such two-bit gates in a physical system with very long phase breaking (i.e., quantum phase coherence) times. Simpler versions of the gearbox computer could be used to do experiments on Einstein-Podolsky-Rosen states and related entangled quantum states.
引用
@article{arxiv.cond-mat/9407022,
title = {Two-Bit Gates are Universal for Quantum Computation},
author = {David P. Divincenzo},
journal= {arXiv preprint arXiv:cond-mat/9407022},
year = {2009}
}
备注
21 pages, REVTeX 3.0, two .ps figures available from author upon request