Title: Unusual phase boundary of the magnetic-field-tuned valence transition in ${\mathrm{CeOs}}_4{\mathrm{Sb}}_{12}$

Abstract

The phase diagram of the filled skutterudite $$CeOs_4Sb_{12}$$ has been mapped in fields $$μ_0H$$ of up to 60 T and temperatures $$T$$ down to 0.5 K using resistivity, magnetostriction, and megahertz conductivity. The valence transition separating the semimetallic low-$$H$$, low-$$T\mathscr{L}$$ phase from the metallic high-$$H$$, high-$$T\mathscr{H}$$ phase exhibits a very unusual, wedge-shaped phase boundary, with a nonmonotonic gradient alternating between positive and negative. The expected “elliptical” behavior of the phase boundary of a valence transition with $H^2∝T^2$ originates in the $$H$$ and $$T$$ dependence of the free energy of the $$f$$ multiplet. Here, quantum oscillation measurements suggest that additional energy scales associated with a quantum critical point are responsible for the deviation of the phase boundary of $$CeOs_4Sb_{12}$$ from this textbook behavior at high $$H$$ and low $$T$$. The distortion of the low-$$H$$, high-$$T$$ portion of the phase boundary may be associated with the proximity of $$CeOs_4Sb_{12}$$ to a topological semimetal phase induced by uniaxial stress.

Authors:

Götze, K. ;

• Search DOE PAGES for author "Götze, K."
• Search DOE PAGES for ORCID "0000-0001-9108-9490"

Pearce, M. J.; Goddard, P. A. ;

• Search DOE PAGES for author "Goddard, P. A."
• Search DOE PAGES for ORCID "0000-0002-0666-5236"

Jaime, M.; Maple, M. B.; Sasmal, K.; Yanagisawa, T.; McCollam, A.; Khouri, T.; Ho, P. -C.; Singleton, J.

Publication Date:

Sat Feb 01 00:00:00 EST 2020

Research Org.:

Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF); European Research Council (ERC); Japan Society for the Promotion of Science (JSPS); Engineering and Physical Sciences Resource Council (EPSRC); State of Florida

OSTI Identifier:

1596893

Alternate Identifier(s):

OSTI ID: 1634957; OSTI ID: 1829630

Report Number(s):

LA-UR-19-26722; LA-UR-20-21171
Journal ID: ISSN 2469-9950; PRBMDO; 075102

Grant/Contract Number:  

89233218CNA000001; FG02-04ER46105; DMR-1157490; DMR-1644779; DMR-1810310; DMR-1905636; DMR-1506677; 681260; JP15KK0146; JP18H04297; JP17K05525

Resource Type:

Published Article

Journal Name:

Physical Review. B

Additional Journal Information:

Journal Name: Physical Review. B Journal Volume: 101 Journal Issue: 7; Journal ID: ISSN 2469-9950

Publisher:

American Physical Society (APS)

Country of Publication:

United States

Language:

English

Subject:

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; high magnetic field science; electrical conductivity; magnetostriction; phase diagrams; quantum criticality; skutterudites; resistivity measurements