LOW-TEMPERATURE PROPERTIES OF CLASSICAL GEOMETRICALLY FRUSTRATED ANTIFERROMAGNETS

摘要: We study the ground-state and low-energy properties of classical vector spin models with nearest-neighbor antiferromagnetic interactions on a class geometrically frustrated lattices, which includes kagome pyrochlore lattices. explore behavior these magnets that results from their large degeneracies, emphasizing universal features systematic differences between individual models. investigate circumstances under thermal fluctuations select particular subset ground states, find this happens only for smallest degeneracies. For magnets, we give an explicit construction all show they are not separated by internal energy barriers. precessional dynamics Heisenberg antiferromagnet. There is no freezing transition or selection preferred states. Instead, relaxation time at low temperature T order $\ensuremath{\Elzxh}{/k}_{B}T.$ argue can also be expected in some other systems, including model compound ${\mathrm{SrCr}}_{8}{\mathrm{Ga}}_{4}{\mathrm{O}}_{19}.$