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Title: Quantum communication and computing with atomic ensembles using a light-shift-imbalance-induced blockade

Abstract

Recently, we have shown that for conditions under which the so-called light-shift imbalance induced blockade occurs, the collective excitation of an ensemble of a multilevel atom can be treated as a closed two-level system. In this paper, we describe how such a system can be used as a quantum bit (qubit) for quantum communication and quantum computing. Specifically, we show how to realize a controlled-NOT gate using the collective qubit and an easily accessible ring cavity, via an extension of the so-called Pellizzari scheme. We also describe how multiple, small-scale quantum computers realized using these qubits can be linked effectively for implementing a quantum internet. We describe the details of the energy levels and transitions in an {sup 87}Rb atom that could be used for implementing these schemes.

Authors:
; ;  [1]
  1. EECS Department, Northwestern University, Evanston, Illinois 60208 (United States)
Publication Date:
OSTI Identifier:
20982090
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.022323; (c) 2007 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; ATOMS; CAVITY RESONATORS; COLLECTIVE EXCITATIONS; COMMUNICATIONS; ENERGY LEVELS; QUANTUM COMPUTERS; QUBITS; RUBIDIUM 87

Citation Formats

Shahriar, M. S., Pati, G. S., and Salit, K. Quantum communication and computing with atomic ensembles using a light-shift-imbalance-induced blockade. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.022323.
Shahriar, M. S., Pati, G. S., & Salit, K. Quantum communication and computing with atomic ensembles using a light-shift-imbalance-induced blockade. United States. doi:10.1103/PHYSREVA.75.022323.
Shahriar, M. S., Pati, G. S., and Salit, K. Thu . "Quantum communication and computing with atomic ensembles using a light-shift-imbalance-induced blockade". United States. doi:10.1103/PHYSREVA.75.022323.
@article{osti_20982090,
title = {Quantum communication and computing with atomic ensembles using a light-shift-imbalance-induced blockade},
author = {Shahriar, M. S. and Pati, G. S. and Salit, K.},
abstractNote = {Recently, we have shown that for conditions under which the so-called light-shift imbalance induced blockade occurs, the collective excitation of an ensemble of a multilevel atom can be treated as a closed two-level system. In this paper, we describe how such a system can be used as a quantum bit (qubit) for quantum communication and quantum computing. Specifically, we show how to realize a controlled-NOT gate using the collective qubit and an easily accessible ring cavity, via an extension of the so-called Pellizzari scheme. We also describe how multiple, small-scale quantum computers realized using these qubits can be linked effectively for implementing a quantum internet. We describe the details of the energy levels and transitions in an {sup 87}Rb atom that could be used for implementing these schemes.},
doi = {10.1103/PHYSREVA.75.022323},
journal = {Physical Review. A},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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