Lawrence Berkeley National Laboratory
Pressure-resistant intermediate valence in the kondo insulator SmB6
- Author(s): Butch, NP
- Paglione, J
- Chow, P
- Xiao, Y
- Marianetti, CA
- Booth, CH
- Jeffries, JR
- et al.
Published Web Locationhttps://doi.org/10.1103/PhysRevLett.116.156401
© 2016 American Physical Society. Resonant x-ray emission spectroscopy was used to determine the pressure dependence of the f-electron occupancy in the Kondo insulator SmB6. Applied pressure reduces the f occupancy, but surprisingly, the material maintains a significant divalent character up to a pressure of at least 35 GPa. Thus, the closure of the resistive activation energy gap and onset of magnetic order are not driven by stabilization of an integer valent state. Over the entire pressure range, the material maintains a remarkably stable intermediate valence that can in principle support a nontrivial band structure.