Interesting magnetic response of the nuclear fuel material UO2. (1st February 2022)

• Record Type: Journal Article
• Authors: Pal, Sudip; Sharath Chandra, L. S.; Chattopadhyay, Maulindu Kumar; Roy, S. B.
• Is Part Of: Phase transitions. Volume 95:Number 2(2022)
• Page Start: 120
• Page End: 130
• Publication Date: 2022-02-01
• Subjects: Magnetization -- antiferromagnet -- thermomagnetic irreversibility -- magnetic field; Phase transformations (Statistical physics) -- Periodicals; 530.47405
• DOI: 10.1080/01411594.2021.2024826
• Languages: English
• ISSNs: 0141-1594

Abstract

ABSTRACT: We report results of dc magnetization measurements on UO2 . Our study reveals a deviation from standard Curie-Weiss (CW) paramagnetic behavior below 280 K, and that is followed by a transition to antiferromagnetic state with marked thermomagnetic irreversibility below TN = 30.6 K. The zero field cooled (ZFC) magnetization exhibits distinct structures not usually observed in the antiferromagnets, whereas field cooled (FC) magnetization looks more like a ferromagnet. The thermomagnetic irreversibility continues to exist in a subtle way even in the paramagnetic regime well above TN . This behavior along with the deviation from CW law highlight non-standard nature of the paramagnetic state. Magnetic response below TN changes significantly with the increase in the applied magnetic field. In the isothermal magnetic field variation of magnetization, a subtle signature of a magnetic field-induced phase transition is observed. All these experimental results highlight the non-trivial nature of the magnetic state in UO2 .