Direct Measurement of the Magnetocaloric Effect through Time-Dependent Magnetometry

• Type: Article in International Scientific Journal
• Date: 2022

Authors

Raquel Almeida (Author) FCUP; Amorim, C (Author) Other; Amaral, JS (Author) Other; araujo, j. p. (Author) FCUP; Belo, JH (Author) FCUP

Journal

Title: Physical Review Applied

Vol. 18

ISSN: 2331-7019

Publisher: American Physical Society

Indexing

ISI Web of Knowledge - 0 Citations

Scopus - 2 Citations

Other information

Authenticus ID: P-00X-7DY

DOI: 10.1103/physrevapplied.18.024081

Abstract (EN): The magnetocaloric effect of a given material is typically assessed through indirect estimates of the isothermal magnetic entropy change, delta S-M. While estimating the adiabatic temperature difference, delta T-ad, is more relevant from the standpoint of refrigeration device engineering, this requires specialized experimental setups. We here present an approach to directly measure delta T(ad )through time-dependent magnetometry in a commercial superconducting quantum interference device (SQUID) device. We use as reference material gadolinium under a 20-kOe field change, and compare our results with those of the literature. Under nonadiabatic experimental conditions, a remarkably similar delta T-ad(T) curve profile is obtained; however, its peak amplitude is underestimated. With a simple compensation methodology we are able to further approximate the profile of the delta T-ad(T) curve obtaining the peak amplitude, the maximizing temperature, and the FWHM within relative errors of -4%, -0.7%, and 11%, respectively. Our reported approach makes the measurement of both delta S-M(T) and delta T-ad(T) possible with a single instrument, enabling accelerated progress towards new, competitive, and industry-ready materials.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7