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arXiv · 1404.6297

Experimental confirmation of spin gap in antiferromagnetic alternating spin-3/2 chain substances RCrGeO5 (R = Y or 154Sm) by inelastic neutron scattering experiments

M. Hase·M. Soda·T. Masuda·D. Kawana·T. Yokoo·S. Itoh·A. Matsuo·K. Kindo·M. Kohno
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Abstract

A spin-singlet ground state with a spin gap has been discovered in antiferromagnetic spin chain substances when the spin value is 1/2, 1 or 2. To find spin gap (singlet-triplet) excitations in spin-3/2 chain substances, we performed inelastic neutron scattering and magnetization measurements on {\it R}CrGeO$_5$ ({\it R} = Y or Sm) powders. As expected, we observed spin gap excitations and the dispersion relation of the lowest magnetic excitations. We proved that the spin system of Cr$^{3+}$ was an antiferromagnetic alternating spin-3/2 chain.

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M. Hase, M. Soda, T. Masuda, D. Kawana, T. Yokoo, S. Itoh, A. Matsuo, K. Kindo, M. Kohno. 2014-04-25. Experimental confirmation of spin gap in antiferromagnetic alternating spin-3/2 chain substances RCrGeO5 (R = Y or 154Sm) by inelastic neutron scattering experiments. https://doi.org/10.1103/physrevb.90.024416

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