Strong longitudinal magnetic fluctuations near critical end point in UCoAl: A 59Co-NMR study

Hiroki Nohara, Hisashi Kotegawa, Hideki Tou, Tatsuma D. Matsuda, Etsuji Yamamoto, Yoshinori Haga, Zachary Fisk, Yoshichika Onuki, Dai Aoki, Jacques Flouquet

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)

Abstract

We report 59Co-NMR measurements in UCoAl where metamagnetism occurs owing to the enhancement of ferromagnetism by a magnetic field. The metamagnetic transition from a paramagnetic (PM) state to a ferromagnetic state is a first-order transition at low temperatures, but it changes to a crossover at high temperatures on crossing the critical end point (CEP) at Tcep ∼ 12 K. The contrasting behavior between the relaxation rates 1/T 1 and 1/T2 suggests that the longitudinal magnetic fluctuation of the U moments is strongly enhanced, especially near the CEP. A wide diffusion of the fluctuation from the CEP can be confirmed even in the PM state where the magnetic transition does not occur.

Original languageEnglish
Article number093707
Journaljournal of the physical society of japan
Volume80
Issue number9
DOIs
Publication statusPublished - 2011 Sep
Externally publishedYes

Keywords

  • Critical end point
  • Metamagnetism
  • NMR
  • UCoAl

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Strong longitudinal magnetic fluctuations near critical end point in UCoAl: A <sup>59</sup>Co-NMR study'. Together they form a unique fingerprint.

Cite this