Programmable Quantum Gate Arrays

M. A. Nielsen; Isaac L. Chuang

doi:10.1103/PhysRevLett.79.321

Programmable Quantum Gate Arrays

M. A. Nielsen and Isaac L. Chuang

Phys. Rev. Lett. 79, 321 – Published 14 July 1997

Abstract

We show how to construct quantum gate arrays that can be programmed to perform different unitary operations on a data register, depending on the input to some program register. It is shown that a universal quantum gate array—a gate array which can be programmed to perform any unitary operation—exists only if one allows the gate array to operate in a probabilistic fashion. Thus it is not possible to build a fixed, general purpose quantum computer which can be programmed to perform an arbitrary quantum computation.

Received 18 March 1997

DOI:https://doi.org/10.1103/PhysRevLett.79.321

Authors & Affiliations

M. A. Nielsen¹ and Isaac L. Chuang²

¹Center for Advanced Studies, Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131-1156
²Theoretical Astrophysics T-6, Los Alamos National Laboratory, Los Alamos, New Mexico 87545