Low-lying magnetic excitations and magnetocaloric effect of molecular magnet K6[V15As6O42(H2O)] · 8H2O. (28th October 2015)

• Record Type: Journal Article
• Authors: Fu, Zhendong; Xiao, Yinguo; Su, Yixi; Zheng, Yanzhen; Kögerler, Paul; Brückel, Thomas
• Is Part Of: Europhysics letters. Volume 112:Number 2(2015:Oct.)
• Publication Date: 2015-10-28
• Subjects: 75.40.Cx -- 75.30.Sg -- 75.50.Xx; Physics -- Periodicals; Electronic journals; 530.05
• DOI: 10.1209/0295-5075/112/27003
• Languages: English
• ISSNs: 0295-5075

Abstract

Abstract: Low-temperature heat capacity measurements were performed on the molecular nanomagnet (V15). The low-lying magnetic excitations are clearly evidenced by the Schottky anomalies in the specific-heat data. The energy levels determined from the low-temperature observables agree well with the three-spin model for V15. The magnetocaloric effect of V15 is examined. The maximum entropy change of is found for a field change of at . In spite of the low ground-state spin of V15, a drastic entropy change of is observed for a field change of at 0.4 K, which is comparable to the entropy change of some high-spin sub-kelvin magnetic coolers at such low temperatures. Anisotropy and consequent zero-field splitting result in this characteristic of V15 and may open new possibilities in the design of ultra-low-temperature molecular coolers.