INVESTIGADORES
LAMAS Carlos Alberto
artículos
Título:
Broken discrete symmetries in a frustrated honeycomb antiferromagnet
Autor/es:
H. D. ROSALES; D.C. CABRA; C. A. LAMAS; P. PUJOL; M. E. ZHITOMIRSKY
Revista:
PHYSICAL REVIEW B
Editorial:
AMER PHYSICAL SOC
Referencias:
Lugar: New York; Año: 2013 vol. 87 p. 104402 - 104407
ISSN:
1098-0121
Resumen:
We study the magnetic phase diagram of the $J_1$--$J_2$ Heisenberg
antiferromagnet on a honeycomb lattice at the strongly frustrated point
$J_2/J_1=1/2$ using large-scale Monte Carlo simulations. At low
temperatures we find three different field regimes, each characterized
by different broken discrete symmetries. In low magnetic fields up to
$h_{c1}/J_1approx 2.9$ the $Z_3$ rotational lattice symmetry is
spontaneously broken while a 1/2-magnetization plateau is stabilized
around $h_{c2}/J_1=4$. The collinear plateau state and the coplanar
state in higher fields break the $Z_4$ translational symmetry and
correspond to triple-$q$ magnetic structures. The intermediate phase
$h_{c1}<h<h_{c2}$ has an interesting symmetry structure, breaking
simultaneously the $Z_3$ and $Z_4$ symmetries. At much lower
temperatures the spatial broken discrete symmetries coexist with the
quasi long-range order of the transverse spin components.