A DFT + DMFT study of the two-channel quadrupolar Kondo effect in PrV<sub>2</sub>Al<sub>20</sub>
ORAL
Abstract
Praseodymium-based cubic 1-2-20 materials like PrV2Al20 exhibit a strong coupling between Pr 4f states and conduction electrons. They experimentally show traces of a two-channel quadrupolar Kondo effect in competition with quadrupolar ordering and superconductivity [1]. Valence fluctuations on the Pr atom occur between the magnetic quadrupole 4f2 Γ3 doublet and the excited 4f1 configuration with a dipole Kramers-doublet Γ7. This specific setup leads to an exotic two-channel quadrupolar Kondo effect, where the channel degree of freedom carries a dipole moment and the Kondo degree of freedom a quadrupolar moment. A quadrupolar analog to the famous Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction principally allows for quadrupolar ordering in competition with the Kondo singlet formation.
We develop a dynamical mean-field theory (DMFT) with a non-crossing approximation (NCA) local impurity solver, that is able to faithfully capture the exotic two-channel Kondo physics in this class of materials, including a momentum-dependent hybridization. This method is then combined with a density functional theory (DFT) calculation, allowing us to quantitatively compare the results to experimental data down to the Kondo regime. Within this approximation, we calculate several temperature dependent quantities: density of states, band structure and magnetic susceptibility.
[1] For review, see: T. Onimaru and H. Kusunose, J. Phys. Soc. Jpn. 85, 082002 (2016)
We develop a dynamical mean-field theory (DMFT) with a non-crossing approximation (NCA) local impurity solver, that is able to faithfully capture the exotic two-channel Kondo physics in this class of materials, including a momentum-dependent hybridization. This method is then combined with a density functional theory (DFT) calculation, allowing us to quantitatively compare the results to experimental data down to the Kondo regime. Within this approximation, we calculate several temperature dependent quantities: density of states, band structure and magnetic susceptibility.
[1] For review, see: T. Onimaru and H. Kusunose, J. Phys. Soc. Jpn. 85, 082002 (2016)
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Presenters
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Marvin Lenk
Physikalisches Institut & Bethe Center for Theoretical Physics, Universität Bonn, Germany
Authors
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Marvin Lenk
Physikalisches Institut & Bethe Center for Theoretical Physics, Universität Bonn, Germany
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Fei Gao
Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
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Johann Kroha
Univ Bonn, Universität Bonn, Physikalisches Institut & Bethe Center for Theoretical Physics, Universität Bonn, Germany
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Andriy H Nevidomskyy
Rice Univ, Rice University, Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA, Department of Physics and Astronomy, Rice University, TX, USA, Department of Physics and Astronomy, Rice University, Department of Physics & Astronomy, Rice University