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Title: Systematic low-energy effective field theory for electron-doped antiferromagnets

Abstract

In contrast to hole-doped systems which have hole pockets centered at ({+-}({pi}/2a),{+-}({pi}/2a)), in lightly electron-doped antiferromagnets the charged quasiparticles reside in momentum space pockets centered at (({pi}/a),0) or (0,({pi}/a)). This has important consequences for the corresponding low-energy effective field theory of magnons and electrons which is constructed in this paper. In particular, in contrast to the hole-doped case, the magnon-mediated forces between two electrons depend on the total momentum P-vector of the pair. For P-vector=0, the one-magnon exchange potential between two electrons at distance r is proportional to 1/r{sup 4}, while in the hole case, it has a 1/r{sup 2} dependence. The effective theory predicts that spiral phases are absent in electron-doped antiferromagnets.

Authors:
; ; ;  [1];  [2];  [3]
  1. Institute for Theoretical Physics, Bern University, Sidlerstrasse 5, CH-3012 Bern (Switzerland)
  2. Facultad de Ciencias, Universidad de Colima, Bernal Diaz del Castillo 340, Colima Codigo Postal 28045 (Mexico)
  3. Istituto Nazionale di Fisica Nucleare and Dipartimento di Fisica, Universita di Milano-Bicocca, 3 Piazza della Scienza, 20126 Milan (Italy)
Publication Date:
OSTI Identifier:
20951521
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 21; Other Information: DOI: 10.1103/PhysRevB.75.214405; (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; 36 MATERIALS SCIENCE; ANTIFERROMAGNETISM; DOPED MATERIALS; ELECTRONS; EXCHANGE INTERACTIONS; FIELD THEORIES; HOLES; MAGNONS; VECTORS

Citation Formats

Bruegger, C., Kaempfer, F., Moser, M., Wiese, U.-J., Hofmann, C. P., and Pepe, M. Systematic low-energy effective field theory for electron-doped antiferromagnets. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.214405.
Bruegger, C., Kaempfer, F., Moser, M., Wiese, U.-J., Hofmann, C. P., & Pepe, M. Systematic low-energy effective field theory for electron-doped antiferromagnets. United States. doi:10.1103/PHYSREVB.75.214405.
Bruegger, C., Kaempfer, F., Moser, M., Wiese, U.-J., Hofmann, C. P., and Pepe, M. Fri . "Systematic low-energy effective field theory for electron-doped antiferromagnets". United States. doi:10.1103/PHYSREVB.75.214405.
@article{osti_20951521,
title = {Systematic low-energy effective field theory for electron-doped antiferromagnets},
author = {Bruegger, C. and Kaempfer, F. and Moser, M. and Wiese, U.-J. and Hofmann, C. P. and Pepe, M.},
abstractNote = {In contrast to hole-doped systems which have hole pockets centered at ({+-}({pi}/2a),{+-}({pi}/2a)), in lightly electron-doped antiferromagnets the charged quasiparticles reside in momentum space pockets centered at (({pi}/a),0) or (0,({pi}/a)). This has important consequences for the corresponding low-energy effective field theory of magnons and electrons which is constructed in this paper. In particular, in contrast to the hole-doped case, the magnon-mediated forces between two electrons depend on the total momentum P-vector of the pair. For P-vector=0, the one-magnon exchange potential between two electrons at distance r is proportional to 1/r{sup 4}, while in the hole case, it has a 1/r{sup 2} dependence. The effective theory predicts that spiral phases are absent in electron-doped antiferromagnets.},
doi = {10.1103/PHYSREVB.75.214405},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 21,
volume = 75,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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