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DOE OSTI · 1606746

Valence instability across the magnetostructural transition in USb 2

Brubaker, Z. E.·Xiao, Y.·Chow, P.·Kenney-Benson, C.·Smith, J. S.·Cynn, H.·Reynolds, C.·Butch, N. P.·Zieve, R. J.·Jeffries, J. R.
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Abstract

We have performed pressure-dependent x-ray diffraction and resonant x-ray emission spectroscopy experiments on USb 2 to further characterize the antiferromagnetic-ferromagnetic transition occurring near 8 GPa. We have found the magnetic transition coincides with a tetragonal to orthorhombic transition resulting in a 17% volume collapse as well as a transient f-occupation enhancement. Compared to UAs 2 and UAsS, USb 2 shows a reduced bulk modulus and transition pressure and an increased volume collapse at the structural transition. Except for an enhancement across the transition region, the f occupancy decreases steadily from 1.96 to 1.75.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYCondensed Matter & Materials PhysicsElectronic structureMagnetismPhase transitionsPressure effectsPressure techniquesStrongly correlated systemsX-ray absorption spectroscopyX-ray diffractionX-ray emission spectroscopy

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Brubaker, Z. E., Xiao, Y., Chow, P., Kenney-Benson, C., Smith, J. S., Cynn, H., Reynolds, C., Butch, N. P., Zieve, R. J., Jeffries, J. R.. 2020-02-14. Valence instability across the magnetostructural transition in USb 2. https://doi.org/10.1103/physrevb.101.085123

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