Temperature dependent low-field measurements of the magnetocaloric ΔT with sub-mK resolution in small volume and thin film samples
- Arbeitsgruppe Spektroskopie der kondensierten Materie, Ruhr-Universität Bochum, Universitätsstr. 150, 44780 Bochum (Germany)
- Institut für Materialwissenschaft, TU Darmstadt, 64287 Darmstadt (Germany)
- Institut für Werkstoffe, Ruhr-Universität Bochum, Universitätsstr. 150, 44780 Bochum (Germany)
We present temperature dependent ΔT measurements of the magnetocaloric effect in a thin film sample of Gd, employing magnetomodulation and detection of thermal radiation. A bulk sample of the metamagnetic material LaFe{sub 11.05}Co{sub 0.91}Si{sub 1.04} shows a strong broadening of the ΔT peak for increasing field amplitudes between 4 and 45 mT. Bulk Gd in comparison shows only a weak broadening. All investigated samples exhibit a clear quadratic dependence of ΔT on the external field H{sub ext} at the ΔT peak maximum, contrary to earlier predictions. An analytic expression is derived that interpolates between the H{sub ext}{sup 2}-behavior at low and the well-known H{sub ext}{sup 2/3}-behavior at high fields.
- OSTI ID:
- 22415145
- Journal Information:
- Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 3 Vol. 106; ISSN APPLAB; ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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