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This content will become publicly available on November 30, 2017

Title: Candidate Elastic Quantum Critical Point in LaCu6-xAux

In this paper, the structural properties of LaCu6-xAux are studied using neutron diffraction, x-ray diffraction, and heat capacity measurements. The continuous orthorhombic-monoclinic structural phase transition in LaCu6 is suppressed linearly with Au substitution until a complete suppression of the structural phase transition occurs at the critical composition xc=0.3. Heat capacity measurements at low temperatures indicate residual structural instability at xc. The instability is ferroelastic in nature, with density functional theory calculations showing negligible coupling to electronic states near the Fermi level. Finally, the data and calculations presented here are consistent with the zero temperature termination of a continuous structural phase transition suggesting that the LaCu6-xAux series hosts an elastic quantum critical point.
Authors:
 [1] ;  [2] ;  [3] ;  [2] ;  [2] ;  [4] ;  [5] ;  [3] ;  [6] ;  [4] ;  [7] ;  [8] ;  [9]
  1. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Quantum Condensed Matter Division
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
  3. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Material Science & Engineering
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Quantum Condensed Matter Division
  5. Florida State Univ., Tallahassee, FL (United States). National High Magnetic Field Lab.
  6. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy
  7. Univ. of Missouri, Columbia, MO (United States). Dept. of Physics & Astronomy
  8. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy. Dept. of Material Science and Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
  9. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Quantum Condensed Matter Division; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy
Publication Date:
OSTI Identifier:
1335349
Grant/Contract Number:
AC05-00OR22725; AC02-06CH11357; SC0001299; FG02-09ER46577; NA0001979; DMR-1157490
Type:
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 117; Journal Issue: 23; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE National Nuclear Security Administration (NNSA); National Science Foundation (NSF); State of Florida (United States)
Contributing Orgs:
Florida State Univ., Tallahassee, FL (United States); Univ. of Missouri, Columbia, MO (United States)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Elastic Quantum Critical Point; Ferroelastic