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Title: Excitonic Condensation under Spin-Orbit Coupling and BEC-BCS Crossover

Abstract

The condensation of electron-hole pairs is studied at zero temperature and in the presence of a weak spin-orbit coupling (SOC) in coupled quantum wells. Under realistic conditions, a perturbative SOC can have observable effects in the order parameter of the condensate. First, the fermion exchange symmetry is absent. As a result, the condensate spin has no definite parity. Additionally, the excitonic SOC breaks the rotational symmetry yielding a complex order parameter in an unconventional way; i.e., the phase pattern of the order parameter is a function of the condensate density. This is manifested through finite off-diagonal components of the static spin susceptibility, suggesting a new experimental method to confirm an excitonic condensate.

Authors:
 [1];  [2]
  1. Department of Physics and National Nanotechnology Research Center, Bilkent University, 06800 Ankara (Turkey)
  2. Department of Physics, Faculty of Sciences and Arts, Selcuk University, Kampus 42075 Konya (Turkey)
Publication Date:
OSTI Identifier:
20951260
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 16; Other Information: DOI: 10.1103/PhysRevLett.98.166405; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BCS THEORY; BOSE-EINSTEIN CONDENSATION; FERMIONS; HOLES; L-S COUPLING; ORDER PARAMETERS; PARITY; QUANTUM WELLS; SPIN; SYMMETRY

Citation Formats

Hakioglu, T., and Sahin, Mehmet. Excitonic Condensation under Spin-Orbit Coupling and BEC-BCS Crossover. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.166405.
Hakioglu, T., & Sahin, Mehmet. Excitonic Condensation under Spin-Orbit Coupling and BEC-BCS Crossover. United States. doi:10.1103/PHYSREVLETT.98.166405.
Hakioglu, T., and Sahin, Mehmet. Fri . "Excitonic Condensation under Spin-Orbit Coupling and BEC-BCS Crossover". United States. doi:10.1103/PHYSREVLETT.98.166405.
@article{osti_20951260,
title = {Excitonic Condensation under Spin-Orbit Coupling and BEC-BCS Crossover},
author = {Hakioglu, T. and Sahin, Mehmet},
abstractNote = {The condensation of electron-hole pairs is studied at zero temperature and in the presence of a weak spin-orbit coupling (SOC) in coupled quantum wells. Under realistic conditions, a perturbative SOC can have observable effects in the order parameter of the condensate. First, the fermion exchange symmetry is absent. As a result, the condensate spin has no definite parity. Additionally, the excitonic SOC breaks the rotational symmetry yielding a complex order parameter in an unconventional way; i.e., the phase pattern of the order parameter is a function of the condensate density. This is manifested through finite off-diagonal components of the static spin susceptibility, suggesting a new experimental method to confirm an excitonic condensate.},
doi = {10.1103/PHYSREVLETT.98.166405},
journal = {Physical Review Letters},
number = 16,
volume = 98,
place = {United States},
year = {Fri Apr 20 00:00:00 EDT 2007},
month = {Fri Apr 20 00:00:00 EDT 2007}
}
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