JPS Conf. Proc. 30, 011021 (2020) [6 pages]
Proceedings of the International Conference on Strongly Correlated Electron Systems (SCES2019)
Revisiting the Possible 4f7 5d1 Ground State of Gd Impurities in SmB6 by Electron Spin Resonance
1Instituto de Física “Gleb Wataghin”, UNICAMP, 13083-859, Campinas, SP, Brazil
2Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
3Los Alamos National Laboratory, Los Alamos, New Mexico 87545, U.S.A.
4Department of Physics and Astronomy, University of California, Irvine, California 92697, U.S.A.
Received September 17, 2019

The search for topological states in strongly correlated electron systems has renewed the interest in the Kondo insulator SmB6. One of the most intriguing previous results was an anomalous electron spin resonance spectrum in Gd-doped SmB6. This spectrum was attributed to Gd2+ ions because it could be very well decribed by a model considering a change in the valence from Gd3+ to Gd2+, a dynamic Jahn–Teller effect and a 4f7 5d1 ground state in the Hamiltonian. In our work, we have revisited this scenario using electron spin resonance and energy dispersive X-ray spectroscopy measurements. Our results suggest that the resonance is produced by Gd2+ ions; however the resonance stems from an extrinsic oxide impurity phase that lies on the surface of the crystal.

©2020 The Author(s)
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