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Evidence for multimagnon-mediated nuclear spin relaxation in the intertwining double-cain ferrimagnet $Ca_3 Cu_3 (PO_4)_4$

Shoji Yamamoto·Hiromitsu Hori·Yuji Furukawa·Yusuke Nishisaka·Yuzuru Sumida·Kiyotaka Yamada·Ken-ichi Kumagai·Takayuki Asano·Yuji Inagaki
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Abstract

The nuclear spin-lattice relaxation time $T_1$ of $^{31}P$ nuclei in the title compound is measured for the first time and interpreted in terms of a modified spin-wave theory. We establish a novel scenario for one-dimensional ferrimagnetic spin dynamics -- it is three-magnon processes enhanced by exchange scattering, rather than Raman processes, that make the major contribution to $1/T_1$.

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Shoji Yamamoto, Hiromitsu Hori, Yuji Furukawa, Yusuke Nishisaka, Yuzuru Sumida, Kiyotaka Yamada, Ken-ichi Kumagai, Takayuki Asano, Yuji Inagaki. 2006-06-26. Evidence for multimagnon-mediated nuclear spin relaxation in the intertwining double-cain ferrimagnet $Ca_3 Cu_3 (PO_4)_4$. https://doi.org/10.1143/jpsj.75.074703

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