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Title: Finite-size behavior of quantum collective spin systems

Abstract

We discuss the finite size behavior of the adiabatic Dicke model, describing the collective coupling of a set of N two-level atoms (qubits) to a faster (electromagnetic) oscillator mode. The energy eigenstates of this system are shown to be directly related to those of another widely studied collective spin model, the uniaxial one. By employing an approximate continuum approach, we obtain a complete characterization of the properties of the latter, which we then use to evaluate the scaling properties of various observables for the original Dicke model near its quantum phase transition.

Authors:
 [1]; ;  [1];  [2]
  1. Dipartimento di Fisica, Universita della Calabria, I-87036 Arcavacata di Rende (Italy)
  2. (Italy)
Publication Date:
OSTI Identifier:
21388813
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 81; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.81.013818; (c) 2010 The American Physical Society
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; APPROXIMATIONS; ATOMS; COUPLING; EIGENSTATES; OSCILLATORS; PHASE TRANSFORMATIONS; QUBITS; SPIN; ANGULAR MOMENTUM; CALCULATION METHODS; ELECTRONIC EQUIPMENT; EQUIPMENT; INFORMATION; PARTICLE PROPERTIES; QUANTUM INFORMATION

Citation Formats

Liberti, Giuseppe, Piperno, Franco, Plastina, Francesco, and INFN-Gruppo collegato di Cosenza, I-87036 Arcavacata di Rende. Finite-size behavior of quantum collective spin systems. United States: N. p., 2010. Web. doi:10.1103/PHYSREVA.81.013818.
Liberti, Giuseppe, Piperno, Franco, Plastina, Francesco, & INFN-Gruppo collegato di Cosenza, I-87036 Arcavacata di Rende. Finite-size behavior of quantum collective spin systems. United States. doi:10.1103/PHYSREVA.81.013818.
Liberti, Giuseppe, Piperno, Franco, Plastina, Francesco, and INFN-Gruppo collegato di Cosenza, I-87036 Arcavacata di Rende. 2010. "Finite-size behavior of quantum collective spin systems". United States. doi:10.1103/PHYSREVA.81.013818.
@article{osti_21388813,
title = {Finite-size behavior of quantum collective spin systems},
author = {Liberti, Giuseppe and Piperno, Franco and Plastina, Francesco and INFN-Gruppo collegato di Cosenza, I-87036 Arcavacata di Rende},
abstractNote = {We discuss the finite size behavior of the adiabatic Dicke model, describing the collective coupling of a set of N two-level atoms (qubits) to a faster (electromagnetic) oscillator mode. The energy eigenstates of this system are shown to be directly related to those of another widely studied collective spin model, the uniaxial one. By employing an approximate continuum approach, we obtain a complete characterization of the properties of the latter, which we then use to evaluate the scaling properties of various observables for the original Dicke model near its quantum phase transition.},
doi = {10.1103/PHYSREVA.81.013818},
journal = {Physical Review. A},
number = 1,
volume = 81,
place = {United States},
year = 2010,
month = 1
}
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