Excellent magnetocaloric properties of La0.7Ca0.3−xSrxMnO3(0.05⩽x⩽0.25) single crystals
2005; American Institute of Physics; Volume: 86; Issue: 7 Linguagem: Inglês
10.1063/1.1867564
ISSN1520-8842
AutoresManh‐Huong Phan, Seong‐Cho Yu, Nam Hwi Hur,
Tópico(s)Advanced Condensed Matter Physics
ResumoThis letter reports on the superior magnetocaloric properties of La0.7Ca0.3−xSrxMnO3 (x=0.05, 0.10, 0.20, and 0.25) single crystals. Upon 50 kOe applied field, the magnetic entropy changes (ΔSM) reach values of ∼10.5, 7.45, 6.97, and 6.86J∕kgK for x=0.05, 0.10, 0.20, and 0.25 compositions, respectively. The large magnetic entropy changes have been found to occur around 300 K, thus allowing magnetic refrigeration at room temperature. Due to the absence of grains in the single crystals, the ΔSM distribution here is much more uniform than that of gadolinium and polycrystalline manganites, which is desirable for an Ericson-cycle magnetic refrigerator. The single crystals have the large magnetic entropy changes induced by low magnetic field change, which is beneficial for the household application of active magnetic refrigerant (AMR) materials. These results indicate that the present single crystals are excellent candidates as working materials for AMR.
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