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Title: Effects of ground-state hyperfine shifts in quantum computing with rare-earth-metal ions in solids

Abstract

We present an investigation of the effects of constant but random shifts of the ground hyperfine qubit states in the setting of quantum computing with ion doped crystals. Complex hyperbolic secant pulses can be used to transfer ions reliably to electronically excited states, and a perturbative approach is used to analyze the effect of ground-state hyperfine shifts. This analysis shows that the errors due to the hyperfine shift are dynamically suppressed during gate operation, a fact we attribute to the ac Stark shift. Furthermore we present an implementation of a controlled phase gate which is resilient to the effects of the hyperfine shift. Decoherence and decay effects are included in simulations in order to show that a demonstration of quantum gates is feasible over the relevant range of system parameters.

Authors:
;  [1]
  1. Lundbeck Foundation Theoretical Center for Quantum System Research, Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark)
Publication Date:
OSTI Identifier:
20982083
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.022316; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DOPED MATERIALS; EXCITED STATES; GROUND STATES; HYPERFINE STRUCTURE; INTERACTIONS; QUANTUM COMPUTERS; QUANTUM MECHANICS; QUBITS; RANDOMNESS; RARE EARTHS; SIMULATION; SPECTRAL SHIFT; STARK EFFECT

Citation Formats

Tordrup, Karl, and Moelmer, Klaus. Effects of ground-state hyperfine shifts in quantum computing with rare-earth-metal ions in solids. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.022316.
Tordrup, Karl, & Moelmer, Klaus. Effects of ground-state hyperfine shifts in quantum computing with rare-earth-metal ions in solids. United States. doi:10.1103/PHYSREVA.75.022316.
Tordrup, Karl, and Moelmer, Klaus. Thu . "Effects of ground-state hyperfine shifts in quantum computing with rare-earth-metal ions in solids". United States. doi:10.1103/PHYSREVA.75.022316.
@article{osti_20982083,
title = {Effects of ground-state hyperfine shifts in quantum computing with rare-earth-metal ions in solids},
author = {Tordrup, Karl and Moelmer, Klaus},
abstractNote = {We present an investigation of the effects of constant but random shifts of the ground hyperfine qubit states in the setting of quantum computing with ion doped crystals. Complex hyperbolic secant pulses can be used to transfer ions reliably to electronically excited states, and a perturbative approach is used to analyze the effect of ground-state hyperfine shifts. This analysis shows that the errors due to the hyperfine shift are dynamically suppressed during gate operation, a fact we attribute to the ac Stark shift. Furthermore we present an implementation of a controlled phase gate which is resilient to the effects of the hyperfine shift. Decoherence and decay effects are included in simulations in order to show that a demonstration of quantum gates is feasible over the relevant range of system parameters.},
doi = {10.1103/PHYSREVA.75.022316},
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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