TY - JOUR
T1 - NMR study of quantum spin liquid and its phase transition in the organic spin-1/2 triangular lattice antiferromagnet EtMe3Sb[Pd(dmit) 2]2
AU - Maegawa, Satoru
AU - Itou, Tetsuaki
AU - Oyamada, Akira
AU - Kato, Reizo
PY - 2011
Y1 - 2011
N2 - We found by 13C-NMR experiment that a quasi-two-dimensional organic antiferromagnet with spin 1/2 on the triangular lattice, EtMe 3Sb[Pd(dmit)2]2, has no classical magnetic ordering down to 19.4mK, although the magnetic exchange interaction J is 220-250K. The quantum spin liquid state is realized in this material due to the significant spin frustration and quantum fluctuation. The 13C nuclear spin-lattice relaxation rate T1-1 under an external magnetic field of 7.65T indicates that the excitations have no spin gap in this spin liquid phase above 1.0K. Then the relaxation rate exhibits a clear kink at 1.0K, and shows a steep decrease below this temperature proportional to T 2. This clearly shows a continuous phase transition at 1.0K and the steep decrease of the spin fluctuation could show the appearance of the excitation gap in the lower spin liquid phase. The power law but not exponential law of the temperature dependence may imply a nodal gap rather than a full gap.
AB - We found by 13C-NMR experiment that a quasi-two-dimensional organic antiferromagnet with spin 1/2 on the triangular lattice, EtMe 3Sb[Pd(dmit)2]2, has no classical magnetic ordering down to 19.4mK, although the magnetic exchange interaction J is 220-250K. The quantum spin liquid state is realized in this material due to the significant spin frustration and quantum fluctuation. The 13C nuclear spin-lattice relaxation rate T1-1 under an external magnetic field of 7.65T indicates that the excitations have no spin gap in this spin liquid phase above 1.0K. Then the relaxation rate exhibits a clear kink at 1.0K, and shows a steep decrease below this temperature proportional to T 2. This clearly shows a continuous phase transition at 1.0K and the steep decrease of the spin fluctuation could show the appearance of the excitation gap in the lower spin liquid phase. The power law but not exponential law of the temperature dependence may imply a nodal gap rather than a full gap.
UR - http://www.scopus.com/inward/record.url?scp=81055133438&partnerID=8YFLogxK
U2 - 10.1088/1742-6596/320/1/012032
DO - 10.1088/1742-6596/320/1/012032
M3 - Conference article
AN - SCOPUS:81055133438
SN - 1742-6588
VL - 320
JO - Journal of Physics: Conference Series
JF - Journal of Physics: Conference Series
M1 - 012032
T2 - International Conference on Frustration in Condensed Matter, ICFCM
Y2 - 11 January 2011 through 14 January 2011
ER -