Anisotropic spin fluctuations in heavy-fermion superconductor CeCoIn 5: In-NQR and Co-NMR studies

Yu Kawasaki, Shinji Kawasaki, Mitsuharu Yashima, Takeshi Mito, Guo-Qing Zheng, Yoshio Kitaoka, Hiroaki Shishido, Rikio Settai, Yoshinori Haga, Yoshichika Onuki

Research output: Contribution to journalArticle

63 Citations (Scopus)

Abstract

We report In-NQR and Co-NMR experiments of CeCoIn5 that undergoes a superconducting transition with a record high Tc = 2.3 K to date among heavy-fermion superconductors. At zero magnetic field, an anomalous temperature (T) dependence of nuclear spin-lattice relaxation rate 1/T1 of 115In is explained by the relation 1/T1 ∝ T · χQ(T)3/4 based on the anisotropic spin-fluctuations model in case of the proximity to an antiferromagnetic (AFM) quantum critical point (QCP). The novel behavior of 1/T1 ∼ T 1/4 over a wide T range of Tc <T <40 K arises because the staggered susceptibility almost follows the Curie law χQ(T) ∝ 1/(T + θ) with θ = 0.6 K and hence 1/T1 ∝ T/(T + 0.6)3/4 ∼ T1/4 for θ <T. We highlight that the behavior 1/T1 ∼ T 1/4 is due to the proximity to the anisotropic AFM QCP relevant with its layered structure, and is not associated with the AFM QCP for isotropic 3D systems. We have also found that the AFM spin fluctuations in CeCoIn5 are suppressed by small magnetic field so that θ = 0.6 K at H = 0 increases to θ = 2.5 K at H = 1.1 T, reinforcing that CeCoIn5 is closely located at the QCP.

Original languageEnglish
Pages (from-to)2308-2311
Number of pages4
JournalJournal of the Physical Society of Japan
Volume72
Issue number9
DOIs
Publication statusPublished - Sep 2003
Externally publishedYes

Fingerprint

heavy fermion superconductors
critical point
nuclear magnetic resonance
proximity
magnetic fields
spin-lattice relaxation
nuclear spin
magnetic permeability
temperature

Keywords

  • Heavy fermion
  • Nuclear magnetic resonance
  • Superconductivity

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Anisotropic spin fluctuations in heavy-fermion superconductor CeCoIn 5 : In-NQR and Co-NMR studies. / Kawasaki, Yu; Kawasaki, Shinji; Yashima, Mitsuharu; Mito, Takeshi; Zheng, Guo-Qing; Kitaoka, Yoshio; Shishido, Hiroaki; Settai, Rikio; Haga, Yoshinori; Onuki, Yoshichika.

In: Journal of the Physical Society of Japan, Vol. 72, No. 9, 09.2003, p. 2308-2311.

Research output: Contribution to journalArticle

Kawasaki, Y, Kawasaki, S, Yashima, M, Mito, T, Zheng, G-Q, Kitaoka, Y, Shishido, H, Settai, R, Haga, Y & Onuki, Y 2003, 'Anisotropic spin fluctuations in heavy-fermion superconductor CeCoIn 5: In-NQR and Co-NMR studies', Journal of the Physical Society of Japan, vol. 72, no. 9, pp. 2308-2311. https://doi.org/10.1143/JPSJ.72.2308
Kawasaki, Yu ; Kawasaki, Shinji ; Yashima, Mitsuharu ; Mito, Takeshi ; Zheng, Guo-Qing ; Kitaoka, Yoshio ; Shishido, Hiroaki ; Settai, Rikio ; Haga, Yoshinori ; Onuki, Yoshichika. / Anisotropic spin fluctuations in heavy-fermion superconductor CeCoIn 5 : In-NQR and Co-NMR studies. In: Journal of the Physical Society of Japan. 2003 ; Vol. 72, No. 9. pp. 2308-2311.
@article{9e5a892185d14c88bb3ccac9084ae420,
title = "Anisotropic spin fluctuations in heavy-fermion superconductor CeCoIn 5: In-NQR and Co-NMR studies",
abstract = "We report In-NQR and Co-NMR experiments of CeCoIn5 that undergoes a superconducting transition with a record high Tc = 2.3 K to date among heavy-fermion superconductors. At zero magnetic field, an anomalous temperature (T) dependence of nuclear spin-lattice relaxation rate 1/T1 of 115In is explained by the relation 1/T1 ∝ T · χQ(T)3/4 based on the anisotropic spin-fluctuations model in case of the proximity to an antiferromagnetic (AFM) quantum critical point (QCP). The novel behavior of 1/T1 ∼ T 1/4 over a wide T range of Tc <T <40 K arises because the staggered susceptibility almost follows the Curie law χQ(T) ∝ 1/(T + θ) with θ = 0.6 K and hence 1/T1 ∝ T/(T + 0.6)3/4 ∼ T1/4 for θ <T. We highlight that the behavior 1/T1 ∼ T 1/4 is due to the proximity to the anisotropic AFM QCP relevant with its layered structure, and is not associated with the AFM QCP for isotropic 3D systems. We have also found that the AFM spin fluctuations in CeCoIn5 are suppressed by small magnetic field so that θ = 0.6 K at H = 0 increases to θ = 2.5 K at H = 1.1 T, reinforcing that CeCoIn5 is closely located at the QCP.",
keywords = "Heavy fermion, Nuclear magnetic resonance, Superconductivity",
author = "Yu Kawasaki and Shinji Kawasaki and Mitsuharu Yashima and Takeshi Mito and Guo-Qing Zheng and Yoshio Kitaoka and Hiroaki Shishido and Rikio Settai and Yoshinori Haga and Yoshichika Onuki",
year = "2003",
month = "9",
doi = "10.1143/JPSJ.72.2308",
language = "English",
volume = "72",
pages = "2308--2311",
journal = "Journal of the Physical Society of Japan",
issn = "0031-9015",
publisher = "Physical Society of Japan",
number = "9",

}

TY - JOUR

T1 - Anisotropic spin fluctuations in heavy-fermion superconductor CeCoIn 5

T2 - In-NQR and Co-NMR studies

AU - Kawasaki, Yu

AU - Kawasaki, Shinji

AU - Yashima, Mitsuharu

AU - Mito, Takeshi

AU - Zheng, Guo-Qing

AU - Kitaoka, Yoshio

AU - Shishido, Hiroaki

AU - Settai, Rikio

AU - Haga, Yoshinori

AU - Onuki, Yoshichika

PY - 2003/9

Y1 - 2003/9

N2 - We report In-NQR and Co-NMR experiments of CeCoIn5 that undergoes a superconducting transition with a record high Tc = 2.3 K to date among heavy-fermion superconductors. At zero magnetic field, an anomalous temperature (T) dependence of nuclear spin-lattice relaxation rate 1/T1 of 115In is explained by the relation 1/T1 ∝ T · χQ(T)3/4 based on the anisotropic spin-fluctuations model in case of the proximity to an antiferromagnetic (AFM) quantum critical point (QCP). The novel behavior of 1/T1 ∼ T 1/4 over a wide T range of Tc <T <40 K arises because the staggered susceptibility almost follows the Curie law χQ(T) ∝ 1/(T + θ) with θ = 0.6 K and hence 1/T1 ∝ T/(T + 0.6)3/4 ∼ T1/4 for θ <T. We highlight that the behavior 1/T1 ∼ T 1/4 is due to the proximity to the anisotropic AFM QCP relevant with its layered structure, and is not associated with the AFM QCP for isotropic 3D systems. We have also found that the AFM spin fluctuations in CeCoIn5 are suppressed by small magnetic field so that θ = 0.6 K at H = 0 increases to θ = 2.5 K at H = 1.1 T, reinforcing that CeCoIn5 is closely located at the QCP.

AB - We report In-NQR and Co-NMR experiments of CeCoIn5 that undergoes a superconducting transition with a record high Tc = 2.3 K to date among heavy-fermion superconductors. At zero magnetic field, an anomalous temperature (T) dependence of nuclear spin-lattice relaxation rate 1/T1 of 115In is explained by the relation 1/T1 ∝ T · χQ(T)3/4 based on the anisotropic spin-fluctuations model in case of the proximity to an antiferromagnetic (AFM) quantum critical point (QCP). The novel behavior of 1/T1 ∼ T 1/4 over a wide T range of Tc <T <40 K arises because the staggered susceptibility almost follows the Curie law χQ(T) ∝ 1/(T + θ) with θ = 0.6 K and hence 1/T1 ∝ T/(T + 0.6)3/4 ∼ T1/4 for θ <T. We highlight that the behavior 1/T1 ∼ T 1/4 is due to the proximity to the anisotropic AFM QCP relevant with its layered structure, and is not associated with the AFM QCP for isotropic 3D systems. We have also found that the AFM spin fluctuations in CeCoIn5 are suppressed by small magnetic field so that θ = 0.6 K at H = 0 increases to θ = 2.5 K at H = 1.1 T, reinforcing that CeCoIn5 is closely located at the QCP.

KW - Heavy fermion

KW - Nuclear magnetic resonance

KW - Superconductivity

UR - http://www.scopus.com/inward/record.url?scp=10744228650&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=10744228650&partnerID=8YFLogxK

U2 - 10.1143/JPSJ.72.2308

DO - 10.1143/JPSJ.72.2308

M3 - Article

AN - SCOPUS:10744228650

VL - 72

SP - 2308

EP - 2311

JO - Journal of the Physical Society of Japan

JF - Journal of the Physical Society of Japan

SN - 0031-9015

IS - 9

ER -