Quantum logic gates from timedependent global magnetic field in a system with constant exchange
Abstract
We propose a method that implements a universal set of one and twoquantumbit gates for quantum computation in a system of coupled electron pairs with constant nondiagonal exchange interaction. In our proposal, suppression of the exchange interaction is performed by the continual repetition of singlespin rotations. A small gfactor difference between the electrons allows for addressing qubits and avoiding strong magnetic field pulses. Numerical experiments were performed to show that, to implement the one and twoqubit operations, it is sufficient to change the strength of the magnetic field by a few Gauss. This introduces one and then the other electron in a resonance. To determine the evolution of the twoqubit system, we use the algorithms of optimal control theory.
 Authors:
 Rzhanov Institute of Semiconductor Physics SB RAS, 630090 Novosibirsk (Russian Federation)
 (Russian Federation)
 Institute for System Dynamics and Control Theory SB RAS, 664033 Irkutsk (Russian Federation)
 Publication Date:
 OSTI Identifier:
 22399304
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 11; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALGORITHMS; ELECTRON PAIRS; ELECTRONS; EXCHANGE INTERACTIONS; LANDE FACTOR; MAGNETIC FIELDS; OPTIMAL CONTROL; QUANTUM COMPUTERS; QUBITS; ROTATION; SPIN; TIME DEPENDENCE
Citation Formats
Nenashev, A. V., Email: nenashev@isp.nsc.ru, Dvurechenskii, A. V., Novosibirsk State University, 630090 Novosibirsk, Zinovieva, A. F., Gornov, A. Yu., and Zarodnyuk, T. S. Quantum logic gates from timedependent global magnetic field in a system with constant exchange. United States: N. p., 2015.
Web. doi:10.1063/1.4915347.
Nenashev, A. V., Email: nenashev@isp.nsc.ru, Dvurechenskii, A. V., Novosibirsk State University, 630090 Novosibirsk, Zinovieva, A. F., Gornov, A. Yu., & Zarodnyuk, T. S. Quantum logic gates from timedependent global magnetic field in a system with constant exchange. United States. doi:10.1063/1.4915347.
Nenashev, A. V., Email: nenashev@isp.nsc.ru, Dvurechenskii, A. V., Novosibirsk State University, 630090 Novosibirsk, Zinovieva, A. F., Gornov, A. Yu., and Zarodnyuk, T. S. 2015.
"Quantum logic gates from timedependent global magnetic field in a system with constant exchange". United States.
doi:10.1063/1.4915347.
@article{osti_22399304,
title = {Quantum logic gates from timedependent global magnetic field in a system with constant exchange},
author = {Nenashev, A. V., Email: nenashev@isp.nsc.ru and Dvurechenskii, A. V. and Novosibirsk State University, 630090 Novosibirsk and Zinovieva, A. F. and Gornov, A. Yu. and Zarodnyuk, T. S.},
abstractNote = {We propose a method that implements a universal set of one and twoquantumbit gates for quantum computation in a system of coupled electron pairs with constant nondiagonal exchange interaction. In our proposal, suppression of the exchange interaction is performed by the continual repetition of singlespin rotations. A small gfactor difference between the electrons allows for addressing qubits and avoiding strong magnetic field pulses. Numerical experiments were performed to show that, to implement the one and twoqubit operations, it is sufficient to change the strength of the magnetic field by a few Gauss. This introduces one and then the other electron in a resonance. To determine the evolution of the twoqubit system, we use the algorithms of optimal control theory.},
doi = {10.1063/1.4915347},
journal = {Journal of Applied Physics},
number = 11,
volume = 117,
place = {United States},
year = 2015,
month = 3
}

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