INVESTIGADORES
GRIGERA Santiago Andres
congresos y reuniones científicas
Título:
Charge ordering in a pure spin model: spin-ice
Autor/es:
S. A. GRIGERA
Lugar:
Buenos aires
Reunión:
Congreso; X-LAW3M; 2013
Resumen:
In this talk we discuss the dipolar spin-ice model at xed density of single excitations, , where processes of creation and
annihilation of such excitations are banned. In the very dilute limit this model coincides with the usual dipolar spin-ice
model at low temperatures, with the additional advantage that a negligible number of monopoles allows for equilibration
even at the lowest temperatures. Thus, the transition to the ordered fundamental state found by Melko et al in 2001 is
reached using simple local spin
ip dynamics. As the density is increased, the monopolar nature of the excitations becomes
apparent: the system shows a rich vs. T phase diagram with \charge" ordering transitions analogous to that observed
for Coulomb charges in lattices. A further layer of complexity is revealed by the existence of order both within the charges
and their associated vacuum, which can only be described in terms of spins {the true microscopic degrees of freedom of the
system.