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Title: Arbitrary state controlled-unitary gate by adiabatic passage

Abstract

We propose a fast scheme involving atoms fixed in an optical cavity to directly implement the universal controlled-unitary gate. The present technique based on adiabatic passage uses dark states well suited for the controlled-rotation operation. We show that these dark states allow the robust implementation of a gate that is a generalization of the controlled-unitary gate to the case where the control qubit can be selected to be an arbitrary state. This gate has potential applications to the rapid implementation of quantum algorithms such as the projective measurement algorithm. This process is decoherence-free since excited atomic states and cavity modes are not populated during the dynamics.

Authors:
; ;  [1];  [2]
  1. Laboratoire de Physique, Universite de Bourgogne, UMR CNRS 5027, Boite Postale 47870, 21078 Dijon Cedex (France)
  2. Fachbereich Physik, Universitaet Kaiserslautern, 67653, Kaiserslautern (Germany)
Publication Date:
OSTI Identifier:
20787094
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.73.042321; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ALGORITHMS; ATOMS; CONTROL; EXCITED STATES; GATING CIRCUITS; QUANTUM MECHANICS; QUBITS; ROTATION

Citation Formats

Lacour, X., Guerin, S., Jauslin, H. R., and Sangouard, N. Arbitrary state controlled-unitary gate by adiabatic passage. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Lacour, X., Guerin, S., Jauslin, H. R., & Sangouard, N. Arbitrary state controlled-unitary gate by adiabatic passage. United States. doi:10.1103/PHYSREVA.73.0.
Lacour, X., Guerin, S., Jauslin, H. R., and Sangouard, N. Sat . "Arbitrary state controlled-unitary gate by adiabatic passage". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20787094,
title = {Arbitrary state controlled-unitary gate by adiabatic passage},
author = {Lacour, X. and Guerin, S. and Jauslin, H. R. and Sangouard, N.},
abstractNote = {We propose a fast scheme involving atoms fixed in an optical cavity to directly implement the universal controlled-unitary gate. The present technique based on adiabatic passage uses dark states well suited for the controlled-rotation operation. We show that these dark states allow the robust implementation of a gate that is a generalization of the controlled-unitary gate to the case where the control qubit can be selected to be an arbitrary state. This gate has potential applications to the rapid implementation of quantum algorithms such as the projective measurement algorithm. This process is decoherence-free since excited atomic states and cavity modes are not populated during the dynamics.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 4,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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