Composition dependence of magnetocaloric effect in Sm 1 - x Sr x MnO 3 ( x = 0 . 3 - 0 . 5 )
نویسنده
چکیده
We investigated magnetic and magnetocaloric properties in Sm1-xSrxMnO3 (x = 0.300.5). We report a magnetic field driven first-order metamagnetic transition in the paramagnetic state in x = 0.4 and 0.5 and a second-order transition in x = 0.3. The highest magnetic entropy (-Sm = 6.2 J/kgK for H = 5 T at T = 125 K) that occurs in x = 0.4 is associated with the metamagnetic transition resulting from the field-induced growth and coalescence of ferromagnetic nano clusters preexisting in the paramagnetic state. Our results suggest that manganites with intrinsic nanoscale phase separation can be exploited for magnetic refrigeration. PACS number(s): 75.47. Lx, 65.40.gd, 75.47.Gk
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