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The magnetic entropy change (DeltaS), a measure of the magnetocaloric effect, in Tb5Si3, a compound exhibiting unusual positive magnetoresistance following a magnetic-field-induced transition below magnetic transition temperature (~ 69 K), has been investigated. We found that DeltaS is negative in the paramagnetic state. At the magnetic transition temperature, DeltaS shows sign reversal from negative (in the paramagnetic state) to positive value in the magnetically ordered state. The high-field state which is interestingly the high resistive state is found to be associated with higher entropy i.e. large positive DeltaS, behaving like a paramagnet. On the basis of this observation, we conclude that the magnetic field induces magnetic fluctuations in the system resulting in positive magnetoresistance, thereby rendering support to the idea of inverse metamagnetism in this compound. In addition, we note that Arrott plots present an interesting scenario.
The compound, Tb5Si3, crystallizing in Mn5Si3-type hexagonal structure, was recently reported by us to exhibit a sudden and huge enhancement in electrical resistivity (rho) at a critical magnetic field (H_cr) in the magnetically ordered state (<70 K)
Water ice and spin ice are important model systems in which theory can directly account for zero point entropy associated with quenched configurational disorder. Spin ice differs from water ice in the important respect that its fundamental constituen
We report that the major features in the temperature dependence of dc and ac magnetization of a well-known spin-chain compound, Ca3Co2O6, which has been known to exhibit two complex magnetic transitions due to geometrical frustration (one near 24 K a
In correlated electron systems such as cuprate superconductors and colossal magnetoresistive (CMR) oxides there is often a tendency for a nanoscale self-organization of electrons that can give rise to exotic properties and to extreme non-linear respo
We report the observation of large magnetocaloric effect near room temperature in antipervoskite SnCMn3. The maximal magnetic entropy change at the first-order ferrimagnetic-paramagnetic transition temperature (TC 279 K) is about 80.69mJ/cm3 K and 13