Numerical Modeling of the Central Spin Problem Using the SpinCoherentState P Representation
Abstract
In this work, we consider decoherence of a central spin by a spin bath. In order to study the nonperturbative decoherence regimes, we develop an efficient meanfieldbased method for modeling the spinbath decoherence, based on the P representation of the central spin density matrix. The method can be applied to longitudinal and transverse relaxation at different external fields. In particular, by modeling largesize quantum systems (up to 16 000 bath spins), we make controlled predictions for the slow longtime decoherence of the central spin.
 Authors:
 ORNL
 Ames Laboratory
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC)
 OSTI Identifier:
 1003653
 DOE Contract Number:
 DEAC0500OR22725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review Letters; Journal Volume: 97; Journal Issue: 3
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DENSITY MATRIX; RELAXATION; SIMULATION; SPIN; numerical modeling; central spin; spin coherent state p
Citation Formats
Al Hassanieh, Khaled A, Dobrovitski, V. V., Dagotto, Elbio R, and Harmon, B. N.. Numerical Modeling of the Central Spin Problem Using the SpinCoherentState P Representation. United States: N. p., 2006.
Web. doi:10.1103/PhysRevLett.97.037204.
Al Hassanieh, Khaled A, Dobrovitski, V. V., Dagotto, Elbio R, & Harmon, B. N.. Numerical Modeling of the Central Spin Problem Using the SpinCoherentState P Representation. United States. doi:10.1103/PhysRevLett.97.037204.
Al Hassanieh, Khaled A, Dobrovitski, V. V., Dagotto, Elbio R, and Harmon, B. N.. Sun .
"Numerical Modeling of the Central Spin Problem Using the SpinCoherentState P Representation". United States.
doi:10.1103/PhysRevLett.97.037204.
@article{osti_1003653,
title = {Numerical Modeling of the Central Spin Problem Using the SpinCoherentState P Representation},
author = {Al Hassanieh, Khaled A and Dobrovitski, V. V. and Dagotto, Elbio R and Harmon, B. N.},
abstractNote = {In this work, we consider decoherence of a central spin by a spin bath. In order to study the nonperturbative decoherence regimes, we develop an efficient meanfieldbased method for modeling the spinbath decoherence, based on the P representation of the central spin density matrix. The method can be applied to longitudinal and transverse relaxation at different external fields. In particular, by modeling largesize quantum systems (up to 16 000 bath spins), we make controlled predictions for the slow longtime decoherence of the central spin.},
doi = {10.1103/PhysRevLett.97.037204},
journal = {Physical Review Letters},
number = 3,
volume = 97,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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