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Nuclear Magnetic Relaxation in the Haldane-Gap Antiferromagnet Ni(C_2_H_8_N_2_)_2_NO_2_(ClO_4_)

Shoji Yamamoto·Hiromitsu Hori
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Abstract

A new theory is proposed to interpret nuclear spin-lattice relaxation-time (T_1_) measurements on the spin-1 quasi-one-dimensional Heisenberg antiferromagnet Ni(C_2_H_8_N_2_)_2_NO_2_(ClO_4_) (NENP). While Sagi and Affleck pioneeringly discussed this subject in terms of field-theoretical languages, there is no theoretical attempt yet to explicitly simulate the novel observations of 1/T_1_ reported by Fujiwara et al.. By means of modified spin waves, we solve the minimum of 1/T_1_ as a function of an applied field, pending for the past decade.

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Shoji Yamamoto, Hiromitsu Hori. 2004-01-24. Nuclear Magnetic Relaxation in the Haldane-Gap Antiferromagnet Ni(C_2_H_8_N_2_)_2_NO_2_(ClO_4_). https://doi.org/10.1143/jpsj.73.822

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