Pressure-induced anomalous valence crossover in cubic YbCu5-based compounds

Journal Article · 19 July 2017 · Scientific Reports

DOI: https://doi.org/10.1038/s41598-017-06190-3 · OSTI ID:1624310

Yamaoka, Hitoshi ^[1]; Tsujii, Naohito  ^[2]; Suzuki, Michi-To ^[3]; Yamamoto, Yoshiya ^[4]; Jarrige, Ignace ^[5]; Sato, Hitoshi ^[6]; Lin, Jung-Fu ^[7]; Mito, Takeshi ^[8]; Mizuki, Jun’ichiro ^[4]; Sakurai, Hiroya ^[9]; Sakai, Osamu ^[9]; Hiraoka, Nozomu ^[10]; Ishii, Hirofumi ^[10]; Tsuei, Ku-Ding ^[10]; Giovannini, Mauro  ^[11]; Bauer, Ernst ^[12]

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1. RIKEN, Hyogo (Japan). RIKEN SPring-8 Center
2. National Inst. of Materials Science, Ibaraki (Japan). International Center for Materials Nanoarchitectonics (MANA)
3. RIKEN Center for Emergent Matter Science, Saitama (Japan)
4. Kwansei Gakuin Univ., Hyogo (Japan). Graduate School of Science and Technology
5. Brookhaven National Lab. (BNL), Upton, NY (United States). Photon Sciences Directorate
6. Hirosaki Univ. (Japan). HiSOR
7. Univ. of Texas, Austin, TX (United States). Dept. of Geological Sciences; Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai (China)
8. Univ. of Hyogo (Japan). Graduate School of Material Science
9. National Inst. for Materials Science (NIMS), Tsukuba (Japan)
10. National Synchrotron Radiation Research Center, Hsinchu (Taiwan)
11. Univ. of Genova (Italy). CNR-SPIN. Dipartimento di Chimica e Chimica Industriale
12. Vienna Univ. of Technology (Austria). Inst. of Solid State Physics

A pressure-induced anomalous valence crossover without structural phase transition is observed in archetypal cubic YbCu5 based heavy Fermion systems. The Yb valence is found to decrease with increasing pressure, indicating a pressure-induced crossover from a localized 4f13 state to the valence fluctuation regime, which is not expected for Yb systems with conventional c–f hybridization. This result further highlights the remarkable singularity of the valence behavior in compressed YbCu5- based compounds. The intermetallics Yb2Pd2Sn, which shows two quantum critical points (QCP) under pressure and has been proposed as a potential candidate for a reentrant Yb2+ state at high pressure, was also studied for comparison. In this compound, the Yb valence monotonically increases with pressure, disproving a scenario of a reentrant non-magnetic Yb2+ state at the second QCP.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: SC0012704
• OSTI ID: 1624310
• Journal Information: Scientific Reports, Vol. 7, Issue 1; ISSN 2045-2322
• Publisher: Nature Publishing GroupCopyright Statement
• Country of Publication: United States
• Language: English