Universal quantum computation with ordered spinchain networks
Abstract
It is shown that anisotropic spin chains with gapped bulk excitations and magnetically ordered ground states offer a promising platform for quantum computation, which bridges the conventional singlespinbased qubit concept with recently developed topological Majoranabased proposals. We show how to realize the singlequbit Hadamard, phase, and {pi}/8 gates as well as the twoqubit controllednot (cnot) gate, which together form a faulttolerant universal set of quantum gates. The gates are implemented by judiciously controlling Ising exchange and magnetic fields along a network of spin chains, with each individual qubit furnished by a spinchain segment. A subset of singlequbit operations is geometric in nature, relying on control of anisotropy of spin interactions rather than their strength. We contrast topological aspects of the anisotropic spinchain networks to those of pwave superconducting wires discussed in the literature.
 Authors:
 Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States)
 Department of Physics, University of Basel, Klingelbergstrasse 82, CH4056 Basel (Switzerland)
 Publication Date:
 OSTI Identifier:
 22068677
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 84; Journal Issue: 3; Other Information: (c) 2011 American Institute of Physics; Country of input: Syrian Arab Republic
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; ANISOTROPY; CHAINS; EXCITATION; GEOMETRY; GROUND STATES; INTERACTIONS; MAGNETIC FIELDS; P WAVES; QUANTUM COMPUTERS; QUBITS; SPIN; SUPERCONDUCTING WIRES; TOPOLOGY
Citation Formats
Tserkovnyak, Yaroslav, and Loss, Daniel. Universal quantum computation with ordered spinchain networks. United States: N. p., 2011.
Web. doi:10.1103/PHYSREVA.84.032333.
Tserkovnyak, Yaroslav, & Loss, Daniel. Universal quantum computation with ordered spinchain networks. United States. doi:10.1103/PHYSREVA.84.032333.
Tserkovnyak, Yaroslav, and Loss, Daniel. 2011.
"Universal quantum computation with ordered spinchain networks". United States.
doi:10.1103/PHYSREVA.84.032333.
@article{osti_22068677,
title = {Universal quantum computation with ordered spinchain networks},
author = {Tserkovnyak, Yaroslav and Loss, Daniel},
abstractNote = {It is shown that anisotropic spin chains with gapped bulk excitations and magnetically ordered ground states offer a promising platform for quantum computation, which bridges the conventional singlespinbased qubit concept with recently developed topological Majoranabased proposals. We show how to realize the singlequbit Hadamard, phase, and {pi}/8 gates as well as the twoqubit controllednot (cnot) gate, which together form a faulttolerant universal set of quantum gates. The gates are implemented by judiciously controlling Ising exchange and magnetic fields along a network of spin chains, with each individual qubit furnished by a spinchain segment. A subset of singlequbit operations is geometric in nature, relying on control of anisotropy of spin interactions rather than their strength. We contrast topological aspects of the anisotropic spinchain networks to those of pwave superconducting wires discussed in the literature.},
doi = {10.1103/PHYSREVA.84.032333},
journal = {Physical Review. A},
number = 3,
volume = 84,
place = {United States},
year = 2011,
month = 9
}

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