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We report a detailed study of the electric transport and magnetic properties of the LaNdCaMnO manganite system. Substitution of LaIII by smaller NdIII ions, reduces the mean ionic radius of the A site ion. We have studied samples in the entire range between rich La and rich Nd compounds. Results of DC magnetization and resistivity show that doping destabilize the FM character of the pure La compound and triggers the formation of a phase separated state at intermediate doping. We have also found evidence of a dynamical behaviour within the phase separated state. A phase diagram is constructed, summarizing the effect of chemical substitution on the system.
We measured thermal conductivity, k, thermoelectric power, S, and dc electric conductivity, sigma, of La_{5/8-x}Pr_{x}Ca_{3/8}MnO_{3}, showing an intricate interplay between metallic ferromagnetism (FM) and charge ordering (CO) instability. The chang
We report on DC and pulsed electric field sensitivity of the resistance of mixed valent Mn oxide based La(5/8-y)Pr(y)Ca(3/8)MnO(3) (y = 0.4) single crystals as a function of temperature. The low temperature regime of the resistivity is highly current
We investigate the ultra-sharp jump in the isothermal magnetization and the resistivity in the polycrystalline $Sm_{0.5}(Ca_{0.5-y}Sr_{y})MnO_3$ $(y = 0, 0.1, 0.2, 0.25, 0.3, 0.5)$ compounds. The critical field $(H_{cr})$, required for the ultra-shar
$La_{0.7}Ca_{0.3}MnO_3$ samples were prepared in nano- and polycrystalline forms by sol-gel and solid state reaction methods, respectively, and structurally characterized by synchrotron X-ray diffraction. The magnetic properties determined by ac susc
We have resolved a controversial issue concerning the oxygen-isotope shift of the ferromagnetic transition temperature T_{C} in the manganite La_{0.8}Ca_{0.2}MnO_{3+y}. We show that the giant oxygen-isotope shift of T_C observed in the normal oxygen-