Structural transition and orbital glass physics in near-itinerant CoV 2O 4
In this study, the ferrimagnetic spinel CoV 2O 4 has been a topic of intense recent interest, both as a frustrated insulator with unquenched orbital degeneracy and as a near-itinerant magnet which can be driven metallic with moderate applied pressure. Here, we report on our recent neutron di raction and inelastic scattering measurements on powders with minimal cation site disorder. Our main new result is the identification of a weak (Δa/a ~ 10 –4), first order structural phase transition at T* = 90 K, the same temperature where spin canting was seen in recent single crystal measurements. This transition is characterized by a short-range distortion of oxygen octahedral positions, and inelastic data further establish a weak 1.25meV spin gap at low temperature. Together, these findings provide strong support for the local orbital picture and the existence of an orbital glass state at temperatures below T*.
- Authors:
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[1];
[1];
[2];
[2];
[2];
[2];
[3];
[4];
[1]
- Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Univ. of Tennessee, Knoxville, TN (United States); Florida State Univ., Tallahassee, FL (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
- Publication Date:
- Grant/Contract Number:
- AC05-00OR22725
- Type:
- Accepted Manuscript
- Journal Name:
- Physical Review B
- Additional Journal Information:
- Journal Volume: 93; Journal Issue: 1; Journal ID: ISSN 2469-9950
- Publisher:
- American Physical Society (APS)
- Research Org:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Flux Isotope Reactor (HFIR); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
- Sponsoring Org:
- USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS
- OSTI Identifier:
- 1238026
- Alternate Identifier(s):
- OSTI ID: 1235951; OSTI ID: 1335333