TY - JOUR
T1 - Ground state of the organic spin-liquid material EtMe 3Sb[Pd(dmit)2]2
AU - Itou, Tetsuaki
AU - Oyamada, Akira
AU - Maegawa, Satoru
AU - Kato, Reizo
PY - 2011
Y1 - 2011
N2 - The organic Mott insulator EtMe3Sb[Pd(dmit)2] 2 is a 1/2-spin system on a nearly-regular triangular lattice. It does not show classical antiferromagnetic ordering in spite of strong antiferromagnetic exchange interactions J = 220-250 K, and thus it is regarded as a spin liquid material. We have found that (T1T)-1 of this spin liquid state shows a peak at around 1 K and after that (T 1T)-1 decreases on cooling. This is not attributed to slowing down of the spin dynamics because T2-1 does not show any enhancement down to low temperature limit. Therefore, the decrease of (T1T)-1 is attributed to disappearance of spin excitations, suggesting that magnetic excitations acquire an energy gap at least in some portion of q-space. This indicates that the ground state of the present spin-liquid material is not a state with spinon Fermi surface, where magnetic excitations are fully gapless and thus (T1T)-1 does not decrease down to low temperature limit.
AB - The organic Mott insulator EtMe3Sb[Pd(dmit)2] 2 is a 1/2-spin system on a nearly-regular triangular lattice. It does not show classical antiferromagnetic ordering in spite of strong antiferromagnetic exchange interactions J = 220-250 K, and thus it is regarded as a spin liquid material. We have found that (T1T)-1 of this spin liquid state shows a peak at around 1 K and after that (T 1T)-1 decreases on cooling. This is not attributed to slowing down of the spin dynamics because T2-1 does not show any enhancement down to low temperature limit. Therefore, the decrease of (T1T)-1 is attributed to disappearance of spin excitations, suggesting that magnetic excitations acquire an energy gap at least in some portion of q-space. This indicates that the ground state of the present spin-liquid material is not a state with spinon Fermi surface, where magnetic excitations are fully gapless and thus (T1T)-1 does not decrease down to low temperature limit.
UR - http://www.scopus.com/inward/record.url?scp=81055133437&partnerID=8YFLogxK
U2 - 10.1088/1742-6596/320/1/012033
DO - 10.1088/1742-6596/320/1/012033
M3 - Conference article
AN - SCOPUS:81055133437
SN - 1742-6588
VL - 320
JO - Journal of Physics: Conference Series
JF - Journal of Physics: Conference Series
M1 - 012033
T2 - International Conference on Frustration in Condensed Matter, ICFCM
Y2 - 11 January 2011 through 14 January 2011
ER -