Abstract
Perovskite-type manganites have been studied both experimentally and theoretically since 1950s. The research on these oxides became more attractive after the discovery of colossal mangetoresistance effect (CMR) in the 1990s, in which the resistivity can be dramatically changed under magnetic fields. Besides magnetic field, the properties of manganites can be significantly influenced by other external stimuli, such as electric field, light, pressure, and strain. In this project, the effects of the external perturbations on the transport properties of manganite film La1-xHfxMnO3 (La3+ ions of the parent compound LaMnO3 are partially substituted by tetravalent Hf, LHMO) will be investigated. More specifically, on the macroscopic scale, the strain is introduced into the LHMO film by depositing it on different substrates. The resulted strain in the LHMO film can lead to lattice distortion and also possible bond length change, thus affecting its properties. On the microscopic scale, the carrier concentration in the LHMO film can be modulated by perturbations like electric field, magnetic field, and photo illumination. From the macroscopic and microscopic changes resulted from the multi-field modulation, the transport properties of the LHMO film are investigated systematically.
Anyone interested is welcome to attend.