Pressure dependent intermediate valence behavior in YbNiGa${}_4$ and YbNiIn${}_4$

Abstract

We report a comprehensive structural and valence study of the intermediate valent materials YbNiGa${}_4$ and YbNiIn${}_4$ under pressures up to 60 GPa. YbNiGa${}_4$ undergoes a smooth volume contraction and shows steady increase in Yb-valence with pressure, though the Yb-valence reaches saturation around 25 GPa. In YbNiIn${}_4$, a change in pressure dependence of the volume and a peak in Yb-valence suggest a pressure induced electronic topological transition occurs around 10-14 GPa. In the pressure region where YbNiIn${}_4$ and YbNiGa${}_4$ possess similar Yb-Yb spacings the Yb-valence reveals a precipitous drop. This drop is not captured by density-functional-theory calculations and implies that both the lattice degrees of freedom and the chemical environment play an important role in establishing the valence of Yb.

References in corpus (5)

• Strong valence fluctuation in the quantum critical heavy fermion superconductor beta-YbAlB4: A hard x-ray photoemission study
• Pressure-Induced Valence Crossover and Novel Metamagnetic Behavior near the Antiferromagnetic Quantum Phase Transition of YbNi${}_3$Ga${}_9$
• Lifshitz transition from valence fluctuations in YbAl3
• Exchange energy dominated by large orbital spin-currents in $\delta$-Pu
• Crossover from a heavy fermion to intermediate valence state in noncentrosymmetric Yb2Ni12(P,As)7

Cited by in corpus (3)

• Novel Valence Transition in Elemental Metal Europium around 80 GPa
• Pressure-Driven Valence Increase and Metallization in Kondo Insulator Ce${}_3$Bi${}_4$Pt${}_3$
• Valence instability across magnetostructural transition in USb${}_2$