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The magnetocaloric effect is the isothermal change of magnetic entropy and the adiabatic temperature change induced in a magnetic material when an external magnetic field is applied. In this work, we present an experimental setup to study this effect in metamagnetic transitions, using the differential thermal analysis technique, which consists in measuring simultaneously the temperatures of the sample of interest and a reference one while an external magnetic field ramp is applied. We have tested our system to measure the magnetocaloric effect in La0.305Pr0.32Ca0.375MnO3, which presents phase separation effects at low temperatures (T < 200 K). We obtain DeltaT vs H curves, and analyze how the effect varies by changing the rate of the magnetic field ramp. Our results show that the intensity of the effect increases with the magnetic field change rate. We also have obtained the effective heat capacity of the system without the sample by performing calorimetric measurements using a pulse heat method, fitting the temperature change with a two tau description. With this analysis, we are able to describe the influence of the environment and subtract it to calculate the adiabatic temperature change of the sample.
The criticality-enhanced magnetocaloric effect (MCE) near a field-induced quantum critical point (QCP) in the spin systems constitutes a very promising and highly tunable alternative to conventional adiabatic demagnetization refrigeration. Strong flu
SmB6 is a mixed valence Kondo insulator that exhibits a sharp increase in resistance following an activated behavior that levels off and saturates below 4K. This behavior can be explained by the proposal of SmB6 representing a new state of matter, a
The influence of the grain size in the magnetic properties of phase separated manganites is an important issue evidenced more than a decade ago. The formation of long range ordered phases is suppressed as the grain size decreases giving place to a me
We report a large entropy change (DeltaS) below 300 K, peaking near TC= 220 K, due to isothermal change of magnetic field, for Gd4Co3, with a refrigeration capacity higher than that of Gd. Notably, the isothermal magnetization is nonhysteretic - an i
EuRhAl4Si2, crystallizes in tetragonal crystal structure and orders antiferromagnetically at ~12 K. The isothermal magnetization along the two principle directions is highly anisotropic despite Eu2+ being an S-state ion. The variation of entropy chan