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Title: Universal quantum computation with ordered spin-chain 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 single-spin-based qubit concept with recently developed topological Majorana-based proposals. We show how to realize the single-qubit Hadamard, phase, and {pi}/8 gates as well as the two-qubit controlled-not (cnot) gate, which together form a fault-tolerant 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 spin-chain segment. A subset of single-qubit operations is geometric in nature, relying on control of anisotropy of spin interactions rather than their strength. We contrast topological aspects of the anisotropic spin-chain networks to those of p-wave superconducting wires discussed in the literature.

Authors:
 [1];  [2]
  1. Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States)
  2. Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 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 spin-chain networks. United States: N. p., 2011. Web. doi:10.1103/PHYSREVA.84.032333.
Tserkovnyak, Yaroslav, & Loss, Daniel. Universal quantum computation with ordered spin-chain networks. United States. doi:10.1103/PHYSREVA.84.032333.
Tserkovnyak, Yaroslav, and Loss, Daniel. 2011. "Universal quantum computation with ordered spin-chain networks". United States. doi:10.1103/PHYSREVA.84.032333.
@article{osti_22068677,
title = {Universal quantum computation with ordered spin-chain 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 single-spin-based qubit concept with recently developed topological Majorana-based proposals. We show how to realize the single-qubit Hadamard, phase, and {pi}/8 gates as well as the two-qubit controlled-not (cnot) gate, which together form a fault-tolerant 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 spin-chain segment. A subset of single-qubit operations is geometric in nature, relying on control of anisotropy of spin interactions rather than their strength. We contrast topological aspects of the anisotropic spin-chain networks to those of p-wave 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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