T. Kohmoto

Spin dynamics in the ordered phases of the triangular lattice Heisenberg antiferromagnet CsMnI3

NMR spectrum and nuclear spin relaxation time of 133 Cs in CsMnI 3 were measured to study the spin dynamics in a triangular lattice Heisenberg antiferromagnet. Characteristic motions such as a rotation around the c -axis and a swinging motion of the 120° spin structure were revealed.

Proton nuclear magnetic relaxation in quasi-one-dimensional S=1 Heisenberg antiferromagnet Ni(C2H8N2)2NO2(ClO4)

The proton spin-lattice relaxation time T 1 in the Haldane-gap system, Ni(C 2 H 8 N 2 ) 2 NO 2 (ClO 4 ) was measured down to 0.5 K. The development of antiferromagnetic short range order was not found even at low temperatures. A relaxation process of activation type with an energy gap of 11 K has been observed.

Optical study of nanosecond spin—lattice relaxation in the triplet state of benzil near room temperature

Abstract Nanosecond spin—lattice relaxation (SLR) times are measured in the triplet state of neat benzil near room temperature. The effect of the SLR on the phosphorescence is detected by using a time-correlated single-photon-counting technique from 150 to 288 K. The thermal deactivation of the trap is also investigated. The characteristic energies relevant to the SLR and the deactivation of the trap are 1.3×10 3 and 3.7×10 3 cm −1 , respectively.

Propagation of domain-wall pair in the ordered phase of CsCoCl3

The longitudinal and transverse relaxation times of 133 Cs were measured in the ordered phase of CsCoCl 3 . From an analysis of fluctuating internal field at the Cs nuclei, the experimental results were interpreted in terms of the spin inversion caused by the propagation of domain-wall pair in the Co 2+ chain.

Soliton Dynamics in Impure Ising-like Antiferromagnetic Chains

Solitons in one-dimensional magnetic systems have recently been receiving considerable interest. The soliton behaves like a free particle when the mean free path λ is much longer than the inverse of the soliton density ns (“coherent model”). On the contrary, if the condition nsλ TN2 has been shown by the experiments of ESR [2] and neutron scattering [3].