Magnetothermodynamics of the spin- 1 / 2 Kagome antiferromagnet
In this paper, we use a new hybrid method to compute the thermodynamic behavior of the spin- 1 / 2 Kagome antiferromagnet under the influence of a large external magnetic field. We find a T2 low-temperature behavior and a very low sensitivity of the specific heat to a strong external magnetic field. We display clear evidence that this low-temperature magnetothermal effect is associated with the existence of low-lying fluctuating singlets, but also that the whole picture ( T2 behavior of C(v) and the thermally activated spin susceptibility) implies contribution of both nonmagnetic and magnetic excitations. Comparison with experiments is made.
Sindzingre
P
Laboratoire de Physique Theorique des Liquides, Universite P. et M. Curie, case 121, 4 Place Jussieu, 75252 Paris Cedex, France.
Misguich
G
Lhuillier
C
Bernu
B
Pierre
L
Waldtmann
C
Everts
H