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arXiv:quant-ph/9503005 · Physical Review Letters

Simple Realization of the Fredkin Gate using a Series Of Two-Body Operators

H. F. Chau, Frank A. Wilczek

Published Jul 24, 1995• 59 citations
arXivHTMLPDF

Abstract

The Fredkin three-bit gate is universal for computational logic, and is reversible. Classically, it is impossible to do universal computation using reversible two-bit gates only. Here we construct the Fredkin gate using a combination of six two-body reversible (quantum) operators.
DOI
10.1103/physrevlett.75.748

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We present numerical results which show how two-bit logic gates can be used in the design of a quantum computer. We show that the Toffoli gate, which is the universal gate for all classical reversible computation, can be implemented using a particular sequence of exactly five two-bit gates. An arbitrary three-bit unitary gate, which can be used to build up any arbitrary quantum computation, can be implemented exactly with six two-bit gates. The ease of implementation of any particular quantum operation is dependent upon a very nonclassical feature of the operation, its exact quantum phase factor.>
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