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arXiv · 2010.08636

Hyperfine Couplings as a Probe of Orbital Anisotropy in Heavy Fermion Materials

P. Menegasso·J. C. Souza·I. Vinograd·Z. Wang·S. P. Edwards·P. G. Pagliuso·N. J. Curro·R. R. Urbano
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Abstract

The transferred hyperfine interaction between nuclear and electron spins in an heavy fermion material depends on the hybridization between the $f$-electron orbitals and those surrounding a distant nucleus. In CeMIn$_5$ (M=Rh, Ir, Co), both the hyperfine coupling to the two indium sites as well as the crystalline electric field at the Ce are strongly dependent on the transition metal. We measure a series of CeRh$_{1-x}$Ir$_x$In$_5$ crystals and find that the hyperfine coupling reflects the orbital anisotropy of the ground state Ce 4$f$ wavefunction. These findings provide direct proof that the localized to itinerant transition is dominated by hybridization out of the Ce-In plane in this system.

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P. Menegasso, J. C. Souza, I. Vinograd, Z. Wang, S. P. Edwards, P. G. Pagliuso, N. J. Curro, R. R. Urbano. 2020-10-16. Hyperfine Couplings as a Probe of Orbital Anisotropy in Heavy Fermion Materials. https://doi.org/10.1103/physrevb.104.035154

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