Systematic lowenergy effective field theory for electrondoped antiferromagnets
Abstract
In contrast to holedoped systems which have hole pockets centered at ({+}({pi}/2a),{+}({pi}/2a)), in lightly electrondoped 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 lowenergy effective field theory of magnons and electrons which is constructed in this paper. In particular, in contrast to the holedoped case, the magnonmediated forces between two electrons depend on the total momentum Pvector of the pair. For Pvector=0, the onemagnon 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 electrondoped antiferromagnets.
 Authors:
 Institute for Theoretical Physics, Bern University, Sidlerstrasse 5, CH3012 Bern (Switzerland)
 Facultad de Ciencias, Universidad de Colima, Bernal Diaz del Castillo 340, Colima Codigo Postal 28045 (Mexico)
 Istituto Nazionale di Fisica Nucleare and Dipartimento di Fisica, Universita di MilanoBicocca, 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 lowenergy effective field theory for electrondoped 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 lowenergy effective field theory for electrondoped 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 lowenergy effective field theory for electrondoped antiferromagnets". United States.
doi:10.1103/PHYSREVB.75.214405.
@article{osti_20951521,
title = {Systematic lowenergy effective field theory for electrondoped 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 holedoped systems which have hole pockets centered at ({+}({pi}/2a),{+}({pi}/2a)), in lightly electrondoped 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 lowenergy effective field theory of magnons and electrons which is constructed in this paper. In particular, in contrast to the holedoped case, the magnonmediated forces between two electrons depend on the total momentum Pvector of the pair. For Pvector=0, the onemagnon 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 electrondoped 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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