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Title: Tuning the magnetic ground state of a triangular lattice system

Abstract

The anisotropic triangular lattice of the crednerite system Cu(Mn$$_{1-x}$$Cu$$_{x}$$)O$$_{2}$$ is used as a basic model for studying the influence of spin disorder on the ground state properties of a two-dimensional frustrated antiferromagnet. Neutron diffraction measurements show that the undoped phase (x=0) undergoes a transition to antiferromagnetic long-range order that is stabilized by a frustration-relieving structural distortion. Small deviation from the stoichiometric composition alters the magnetoelastic characteristics and reduces the effective dimensionality of the magnetic lattice. Upon increasing the doping level, the interlayer coupling changes from antiferromagnetic to ferromagnetic, while the structural distortion is fully suppressed. Concomitantly, the long-range magnetic order is gradually transformed into a two-dimensional order.

Authors:
 [1];  [1];  [2]
  1. ORNL
  2. Louisiana State University
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); High Flux Isotope Reactor
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1032469
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 83; Journal Issue: 17
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; GROUND STATES; NEUTRON DIFFRACTION; SPIN; TUNING

Citation Formats

Garlea, Vasile O, Savici, Andrei T, and Jin, Rongying. Tuning the magnetic ground state of a triangular lattice system. United States: N. p., 2011. Web. doi:10.1103/PhysRevB.83.172407.
Garlea, Vasile O, Savici, Andrei T, & Jin, Rongying. Tuning the magnetic ground state of a triangular lattice system. United States. doi:10.1103/PhysRevB.83.172407.
Garlea, Vasile O, Savici, Andrei T, and Jin, Rongying. 2011. "Tuning the magnetic ground state of a triangular lattice system". United States. doi:10.1103/PhysRevB.83.172407.
@article{osti_1032469,
title = {Tuning the magnetic ground state of a triangular lattice system},
author = {Garlea, Vasile O and Savici, Andrei T and Jin, Rongying},
abstractNote = {The anisotropic triangular lattice of the crednerite system Cu(Mn$_{1-x}$Cu$_{x}$)O$_{2}$ is used as a basic model for studying the influence of spin disorder on the ground state properties of a two-dimensional frustrated antiferromagnet. Neutron diffraction measurements show that the undoped phase (x=0) undergoes a transition to antiferromagnetic long-range order that is stabilized by a frustration-relieving structural distortion. Small deviation from the stoichiometric composition alters the magnetoelastic characteristics and reduces the effective dimensionality of the magnetic lattice. Upon increasing the doping level, the interlayer coupling changes from antiferromagnetic to ferromagnetic, while the structural distortion is fully suppressed. Concomitantly, the long-range magnetic order is gradually transformed into a two-dimensional order.},
doi = {10.1103/PhysRevB.83.172407},
journal = {Physical Review Letters},
number = 17,
volume = 83,
place = {United States},
year = 2011,
month = 1
}
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