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Title: Local moments in the heterogeneous electronic state of Cd-substituted CeCoIn 5 : NQR relaxation rates

Abstract

Here, we have used nuclear quadrupole resonance (NQR) to probe microscopically the response of a prototypical quantum critical metal CeCoIn 5 to substitutions of small amounts of Cd for In. Approximately half of the Cd substituents induce local Ce moments in their close proximity, as observed by site-dependent longitudinal nuclear spin relaxation rates 1/T 1. In order to reaffirm that localized f moments are induced around the Cd substituents, we find a Gaussian spin-echo decay rate 1/T 2G of transverse nuclear spin relaxation. Furthermore, $${T}_{1}T/{T}_{2\text{G}}^{2}$$ for the NQR subpeak is found to be proportional to temperatures, again indicating local moments fluctuations around the Cd substituents, while that for the NQR main peak shows a T 0.7-dependence. The latter temperature dependence is close to 0.75 in pure CeCoIn 5 and indicates that the bulk electronic state is located close to a two dimensional quantum critical instability.

Authors:
 [1]; ORCiD logo [2];  [1];  [1];  [1]; ORCiD logo [3];  [2];  [2]; ORCiD logo [2]; ORCiD logo [2]
  1. Japan Atomic Energy Agency (JAEA), Tokai (Japan). Advanced Science Research Center
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Condensed Matter and Magnet Science
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC). Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1375879
Report Number(s):
LA-UR-17-22975
Journal ID: ISSN 1742-6588
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Physics. Conference Series
Additional Journal Information:
Journal Volume: 807; Journal ID: ISSN 1742-6588
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Material Science; NMR, CeCoIn5, inhomogeneity

Citation Formats

Sakai, H., Ronning, F., Hattori, T., Tokunaga, Y., Kambe, S., Zhu, J. -X., Wakeham, N., Yasuoka, H., Bauer, E. D., and Thompson, J. D. Local moments in the heterogeneous electronic state of Cd-substituted CeCoIn 5 : NQR relaxation rates. United States: N. p., 2017. Web. doi:10.1088/1742-6596/807/3/032001.
Sakai, H., Ronning, F., Hattori, T., Tokunaga, Y., Kambe, S., Zhu, J. -X., Wakeham, N., Yasuoka, H., Bauer, E. D., & Thompson, J. D. Local moments in the heterogeneous electronic state of Cd-substituted CeCoIn 5 : NQR relaxation rates. United States. doi:10.1088/1742-6596/807/3/032001.
Sakai, H., Ronning, F., Hattori, T., Tokunaga, Y., Kambe, S., Zhu, J. -X., Wakeham, N., Yasuoka, H., Bauer, E. D., and Thompson, J. D. Thu . "Local moments in the heterogeneous electronic state of Cd-substituted CeCoIn 5 : NQR relaxation rates". United States. doi:10.1088/1742-6596/807/3/032001. https://www.osti.gov/servlets/purl/1375879.
@article{osti_1375879,
title = {Local moments in the heterogeneous electronic state of Cd-substituted CeCoIn 5 : NQR relaxation rates},
author = {Sakai, H. and Ronning, F. and Hattori, T. and Tokunaga, Y. and Kambe, S. and Zhu, J. -X. and Wakeham, N. and Yasuoka, H. and Bauer, E. D. and Thompson, J. D.},
abstractNote = {Here, we have used nuclear quadrupole resonance (NQR) to probe microscopically the response of a prototypical quantum critical metal CeCoIn5 to substitutions of small amounts of Cd for In. Approximately half of the Cd substituents induce local Ce moments in their close proximity, as observed by site-dependent longitudinal nuclear spin relaxation rates 1/T1. In order to reaffirm that localized f moments are induced around the Cd substituents, we find a Gaussian spin-echo decay rate 1/T2G of transverse nuclear spin relaxation. Furthermore, ${T}_{1}T/{T}_{2\text{G}}^{2}$ for the NQR subpeak is found to be proportional to temperatures, again indicating local moments fluctuations around the Cd substituents, while that for the NQR main peak shows a T0.7-dependence. The latter temperature dependence is close to 0.75 in pure CeCoIn5 and indicates that the bulk electronic state is located close to a two dimensional quantum critical instability.},
doi = {10.1088/1742-6596/807/3/032001},
journal = {Journal of Physics. Conference Series},
number = ,
volume = 807,
place = {United States},
year = {Thu Apr 06 00:00:00 EDT 2017},
month = {Thu Apr 06 00:00:00 EDT 2017}
}

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