Global ETD Search

1	Exploration of voltage controlled manganite phase transitions as probed with magnetic force microscopy Ruzicka, Frank Joseph 08 October 2010 (has links) Low-temperature magnetic force microscopy was used to study the phase diagram of a La1/3Pr1/3Ca1/3MnO3 thin film grown on a (110) NdGaO3 (NGO) substrate by pulsed laser deposition. Traditionally, one can observe the phase change at the nanoscale level as the sample is cooled from room temperature through the transition temperature to liquid nitrogen temperatures, but in this case a fixed voltage ranging from 0 V to 31 V was applied before each cooling cycle. From in and ex situ transport measurements, it is observed that the temperature of the peak of the transition increases with applied field; however, the MFM images show that the magnetic transition begins at a lower temperature with the same increase in field. Thus, this dissertation shows that a new voltage control exists for the phase transition in certain manganites. / text AFM MFM LPCMO LSMO Manganites COI FMM PVD Sputtering Cantilever Tip Piezo Scanner tube CMR Strain Jahn-Teller Magnetic imaging