Related papers: Irreversible Heat Flow Across Phase Boundaries in …
The phase transformation kinetics of LaFe$_{11.41}$Mn$_{0.30}$Si$_{1.29}$-H$_{1.65}$ magnetocaloric compound is addressed by low rate calorimetry experiments. Scans at 1 mK/s show that its first order phase transitions are made by multiple…
We observe an interesting scenario of field induced metastabilities in the resistivity measurements. The resistivity exhibits a bifurcation of zero-field cooled and field-cooled (FC) temperature dependence below the paramagnetic to…
We have studied the effect of irreversibility induced by repeated thermal cycles on the electric transport and magnetization of polycrystalline samples of La0.5Ca0.5MnO3 and La0.325Pr0.3Ca0.375MnO3. An increase of the resistivity and a…
Phase-separated manganites provide a unique platform to study the dynamics of competing electronic and structural orders in correlated systems. In La0.275Pr0.35Ca0.375MnO3 (LPCMO), we use temperature-cycling Raman spectroscopy to uncover a…
Dissipation inevitably occurs in first order phase transitions, leading to the irreversible heating. Conversely, the irreversible heating effect could be a clue for the first order phase transition. We measured the temperature change at the…
The magnetic field and temperature dependencies of the magnetic moments of superconducting crystals of ${\rm V_{3}Si}$ have been studied. In a constant magnetic field and at temperatures somewhat below the superconducting transition…
We investigate the behavior of ultrasharp metamagnetic transitions in La(5/8-y)Nd(y)Ca(3/8)MnO(3) manganites. These compounds change from a low temperature ferromagnetic metallic state at low Nd doping to a charge-ordered antiferromagnetic…
The occurrence at low temperatures of an ultrasharp field-induced transition in phase separated manganites is analyzed. Experimental results show that magnetization and specific heat step-like transitions below 5 K are correlated with an…
Neutron powder diffraction studies of the crystal and magnetic structures of the magnetocaloric compound Mn1.1Fe0.9(P0.8Ge0.2) have been carried out as a function of temperature, applied magnetic field, and pressure. The data reveal that…
Magnetoresistance measurements on the quasi one-dimensional organic conductor (TMTSF)_2PF_6 performed in magnetic fields B up to 16T, temperatures T down to 0.12K and under pressures P up to 14kbar have revealed new phases on its P-B-T…
Using two different configurations of temperature and magnetic field gradients, we observed that, in a quasi one-dimensional magnetic fluid, magnetic force either reduces the temperature difference across the sample when the two gradients…
Field variation of heat capacity at fixed temperatures is investigated to identify the origin of the field induced first order phase transition in polycrystalline Ce(Fe$_{0.094}$Al$_{0.04}$)$_2$ sample. The heat capacity at 4.5K and 3.5K…
This is an informal paper that contains a list of ``things we know'' and ``things we do not know'' in manganites. It is adapted from the conclusions chapter of a recent book by the author, {\it Nanoscale Phase Separation and Colossal…
We present high-resolution thermal expansion $\alpha(T)$ and magnetostriction $\Delta L(H)/L$ measurements of GdMnO$_3$, which develops an incommensurate antiferromagnetic order (ICAFM) below $T_{\rm N}\simeq$ 42 K and transforms into a…
The low temperature specific heat C(H) of several rare-earth manganites (La_(0.7)Sr_(0.3)MnO_(3), Nd_(0.5)Sr_(0.5)MnO_(3), Pr_(0.5)Sr_(0.5)MnO_(3), La_(0.67)Ca_(0.33)MnO$_(3), La_(0.5)Ca_(0.5)MnO_(3), La_(0.45)Ca_(0.55)MnO_(3) and…
Magnetization measurements were carried out in the in field-cooled (FC) and in zero-field-cooled (ZFC) conditions versus temperature, T, and external magnetic field, H, on a sigma-phase Fe47Mo53 compound. Analysis of the measured M_FC and…
The thermodynamics of phase transitions between phases that are size-mismatched but coherent differs from conventional stress-free thermodynamics. Most notably, in open systems such phase transitions are always associated with hysteresis.…
We have studied the irreversibility of the magnetization induced by thermal cycles in La0.5Ca0.5MnO3 manganites, which present a low temperature state characterized by the coexistence of phases. The effect is evidenced by a decrease of the…
We present a phenomenological model based on the thermodynamics of the phase separated state of manganites, accounting for its static and dynamic properties. Through calorimetric measurements on La$_{0.225}$Pr$_{0.40}$Ca$ _{0.375}$MnO$_{3}$…
The large magnetocaloric effect in Heusler alloys showing martensite phase transformation puts them forward as efficient materials for magnetic refrigeration. However, irreversibility of the magnetocaloric cooling cycle is a major challenge…