TY - JOUR

T1 - Monte Carlo simulations of the LiHoxY1-xF4 diluted dipolar magnet

AU - Andresen, Juan Carlos

AU - Schechter, Moshe

AU - Katzgraber, Helmut G.

PY - 2012/2/1

Y1 - 2012/2/1

N2 - Recent intriguing experimental results on
LiHoxY1-xF4, a diluted dipolar magnet,
along with new analytical insights, suggest that neither a mean-field
treatment nor simulations using simplified versions of the underlying
Hamiltonian adequately describe these materials. Not only does this
imply that novel disordering mechanism might be present, it requires a
detailed numerical analysis that incorporates all terms in the
Hamiltonian. We present large-scale Monte Carlo simulations of the
diluted dipolar magnet with competing interactions on a LiHo lattice
with the inclusion of a random field term. For low concentrations of Ho
atoms we reproduce the peculiar linear dependence of the transition
temperature as a function of the random-field strength found in recent
experimental results by Silevich et al. [Nature 448, 567 (2007)]. We
then find a zero-temperature phase transition between the ferromagnetic
and quasi-spin-glass phases, suggesting that it is the underlying
spin-glass phase that dictates the above linear dependence of
Tc on the random field. For large concentrations we recover
the quadratic dependence of the critical temperature as a function of
the random field strength.

AB - Recent intriguing experimental results on
LiHoxY1-xF4, a diluted dipolar magnet,
along with new analytical insights, suggest that neither a mean-field
treatment nor simulations using simplified versions of the underlying
Hamiltonian adequately describe these materials. Not only does this
imply that novel disordering mechanism might be present, it requires a
detailed numerical analysis that incorporates all terms in the
Hamiltonian. We present large-scale Monte Carlo simulations of the
diluted dipolar magnet with competing interactions on a LiHo lattice
with the inclusion of a random field term. For low concentrations of Ho
atoms we reproduce the peculiar linear dependence of the transition
temperature as a function of the random-field strength found in recent
experimental results by Silevich et al. [Nature 448, 567 (2007)]. We
then find a zero-temperature phase transition between the ferromagnetic
and quasi-spin-glass phases, suggesting that it is the underlying
spin-glass phase that dictates the above linear dependence of
Tc on the random field. For large concentrations we recover
the quadratic dependence of the critical temperature as a function of
the random field strength.

M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???

JO - American Physical Society, APS March Meeting 2012, February 27-March 2, 2012

JF - American Physical Society, APS March Meeting 2012, February 27-March 2, 2012

ER -