Quantum critical 5f-electrons avoid singularities in U(Ru,Rh)2Si2

Abstract

We present specific heat measurements of 4% Rh-doped U(Ru,Rh)2Si2 at magnetic fields above the proposed metamagnetic transition field Hm~34 T, revealing striking similarities to the isotructural Ce analog CeRu2Si2, suggesting that strongly renormalized hybridized band models apply equally well to both systems. The vanishing bandwidths as H --> Hm are consistent with a putative quantum critical point close to Hm. The existence of a phase transition into an ordered phase in the vicinity of Hm for 4% Rh-doped U(Ru,Rh)2Si2, but not for CeRu2Si2, is consistent with a stronger super-exchange in the case of the U 5-f system, with irreversible processes at the transition revealing a strong coupling of the 5f orbitals to the lattice, most suggestive of orbital or electric quadrupolar order.

4 pages, 4 figures

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Cited by in corpus (8)

• Colloquium: Hidden Order, Superconductivity, and Magnetism -- The Unsolved Case of URu2Si2
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• Phonon Thermal Transport of URu2Si2: Broken Translational Symmetry and Strong-Coupling of the Hidden Order to the Lattice
• Magnetic field-tuned quantum criticality in a Kondo insulator
• Irreversible dynamics of the phase boundary in U(Ru0.9)Rh0.04)2Si2 and implications for ordering
• Strongly correlated Fermi systems as a new state of matter
• Magnetic transitions induced by pressure and magnetic field in a two-orbital $5f$-electron model in cubic and tetragonal lattices