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arXiv · 1209.4613

Anisotropic spin-dynamics in the Kondo semiconductor CeRu2Al10

Julien Robert·Jean-Michel Mignot·Sylvain Petit·Paul Steffens·Takashi Nishioka·Riki Kobayashi·Masahiro Matsumura·Hiroshi Tanida·Daiki Tanaka·Masafumi Sera
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Abstract

Spin dynamics in the new Kondo insulator compound CeRu2Al10 has been studied using unpolarized and polarized neutron scattering on single crystals. In the unconventional ordered phase forming below T0 = 27.3 K, two excitation branches are observed with significant intensities, the lower one of which has a gap of 4.8 +/- 0.3 meV and a pronounced dispersion up to about 8.5 meV. Comparison with RPA magnon calculations assuming crystal-field and anisotropic exchange couplings captures major aspects of the data, but leaves unexplained discrepancies, pointing to a key role of direction-specific hybridization between 4f and conduction band states in this compound.

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Julien Robert, Jean-Michel Mignot, Sylvain Petit, Paul Steffens, Takashi Nishioka, Riki Kobayashi, Masahiro Matsumura, Hiroshi Tanida, Daiki Tanaka, Masafumi Sera. 2012-09-20. Anisotropic spin-dynamics in the Kondo semiconductor CeRu2Al10. https://doi.org/10.1103/physrevlett.109.267208

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