INVESTIGATION OF TEMPERATURE, MAGNETIC FIELD AND TIME DEPENDENT ELECTRICAL TRANSPORT IN PHASE SEPARATED MANGANITE THIN FILMS

Abstract

Abstract Manganites generically represented by RE1-xAExMnO3, where RE and AE are rare earth and alkaline earth cations have engaged the interest of the physics community because of their highly enriched nature regarding the electronic phases. The presence of various phases is demonstrated by the existence paramagnetic insulator (PMI), ferromagnetic metal (FMM), a ferromagnetic insulator (FMI), an antiferromagnetic insulator (AFMI) and charge ordered/orbital ordered (CO/OO) phases. Various parameters (i.e. RE/AE ratio, their average cationic size and thermomagnetic variables etc.) in such materials make the interphase boundaries permeable and cross boundary electronic phase diffusion noticeable. This cross-boundary phase diffusion is called phase separation (PS), which is the axial attribute of the physics of manganites. PS has been recognized as the most striking intrinsic property of doped rare earth manganites. The La1-x-yPryCaxMnO3 has emerged as the generic representative of the manganites showing mesoscale phase separation with coexisting AFMI/CO and FMM cluster. This thesis is devoted on the investigation of temperature, magnetic field and time dependent electrical transport in phase separated manganite thin film. Here, the study of dependence of the insulator metal transition (IMT) of the relative fraction of the two competing phases, nature of the hysteresis in the electrical transport as a function of the thermomagnetic variables temperature (T) and magnetic field (H), temporal evolution of the electrical resistivity, especially near the IMT, and scaling of the hysteresis loop area with temperature and magnetic field on RF magneton sputtered good quality thin films of La1-x-yPryCaxMnO3 on (001) oriented SrTiO3 substrates has been presented.