Field-tuned quasiparticles and electronic structure in heavy-fermion YbNi4P2

Will Broad; Owen Moulding; Takaki Muramatsu; Manuel Brando; Alix McCollam; Femke Bangman; Gertrud Zwicknagl; Kristin Kliemt; Cornelius Krellner; Sven Friedemann

arXiv · 2608.28119

Field-tuned quasiparticles and electronic structure in heavy-fermion YbNi4P2

Will Broad·Owen Moulding·Takaki Muramatsu·Manuel Brando·Alix McCollam·Femke Bangman·Gertrud Zwicknagl·Kristin Kliemt·Cornelius Krellner·Sven Friedemann

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Abstract

We study the Fermi surface topology and quasiparticle properties in the heavy fermion compound YbNi4P2 at high magnetic fields using quantum oscillation measurements. We observe a large decrease of the quasiparticle mass with increasing field and demonstrate good qualitative agreement with the single-ion Kondo model. At the putative Lifshitz transition at 17 T, we observe a sudden change of quantum oscillation frequencies suggesting an abrupt change of the electronic structure and/or quasiparticle characteristics. Our results demonstrate the ability to tune the electronic structure and provide input for theoretical models of YbNi4P2 and correlated electron systems in high magnetic fields.

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Will Broad, Owen Moulding, Takaki Muramatsu, Manuel Brando, Alix McCollam, Femke Bangman, Gertrud Zwicknagl, Kristin Kliemt, Cornelius Krellner, Sven Friedemann. 2026-08-28. Field-tuned quasiparticles and electronic structure in heavy-fermion YbNi4P2. https://arxiv.org/abs/2608.28119

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