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Title: Probing Anomalous Longitudinal Fluctuations of the Interacting Bose Gas via Bose-Einstein Condensation of Magnons

Abstract

The emergence of a finite staggered magnetization in quantum Heisenberg antiferromagnets subject to a uniform magnetic field can be viewed as Bose-Einstein condensation of magnons. Using nonperturbative results for the infrared behavior of the interacting Bose gas, we present exact results for the staggered spin-spin correlation functions of quantum antiferromagnets in a magnetic field at zero temperature. In particular, we show that in dimensions 1<D{<=}3 the longitudinal dynamic structure factor S{sub parallel}(q,{omega}) describing staggered spin fluctuations in the direction of the staggered magnetization exhibits a critical continuum whose weight can be controlled experimentally by varying the magnetic field.

Authors:
; ;  [1]
  1. Institut fuer Theoretische Physik, Universitaet Frankfurt, Max-von-Laue Strasse 1, 60438 Frankfurt (Germany)
Publication Date:
OSTI Identifier:
20955454
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevLett.98.067203; (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; BOSE-EINSTEIN CONDENSATION; BOSE-EINSTEIN GAS; CORRELATION FUNCTIONS; MAGNETIC FIELDS; MAGNETIZATION; MAGNONS; SPIN; STRUCTURE FACTORS

Citation Formats

Kreisel, Andreas, Hasselmann, Nils, and Kopietz, Peter. Probing Anomalous Longitudinal Fluctuations of the Interacting Bose Gas via Bose-Einstein Condensation of Magnons. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.067203.
Kreisel, Andreas, Hasselmann, Nils, & Kopietz, Peter. Probing Anomalous Longitudinal Fluctuations of the Interacting Bose Gas via Bose-Einstein Condensation of Magnons. United States. doi:10.1103/PHYSREVLETT.98.067203.
Kreisel, Andreas, Hasselmann, Nils, and Kopietz, Peter. Fri . "Probing Anomalous Longitudinal Fluctuations of the Interacting Bose Gas via Bose-Einstein Condensation of Magnons". United States. doi:10.1103/PHYSREVLETT.98.067203.
@article{osti_20955454,
title = {Probing Anomalous Longitudinal Fluctuations of the Interacting Bose Gas via Bose-Einstein Condensation of Magnons},
author = {Kreisel, Andreas and Hasselmann, Nils and Kopietz, Peter},
abstractNote = {The emergence of a finite staggered magnetization in quantum Heisenberg antiferromagnets subject to a uniform magnetic field can be viewed as Bose-Einstein condensation of magnons. Using nonperturbative results for the infrared behavior of the interacting Bose gas, we present exact results for the staggered spin-spin correlation functions of quantum antiferromagnets in a magnetic field at zero temperature. In particular, we show that in dimensions 1<D{<=}3 the longitudinal dynamic structure factor S{sub parallel}(q,{omega}) describing staggered spin fluctuations in the direction of the staggered magnetization exhibits a critical continuum whose weight can be controlled experimentally by varying the magnetic field.},
doi = {10.1103/PHYSREVLETT.98.067203},
journal = {Physical Review Letters},
number = 6,
volume = 98,
place = {United States},
year = {Fri Feb 09 00:00:00 EST 2007},
month = {Fri Feb 09 00:00:00 EST 2007}
}
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