IMR: Acquisition of a Measurement System for Research and Education in Thin Film Materials

A Physical Properties Measurement System (PPMS) will be used to investigate the properties of highly correlated and disordered materials. Problems under investigation include the superconductor-insulator transition (SIT) in two dimensions, metal-insulator transitions in oxide film systems, and the nature of superconducting fluctuations in underdoped cuprates. The thin film materials that would be investigated exhibit important paradigms in contemporary condensed matter physics such as quantum criticality and glassiness. The PPMS would complement a series of dedicated facilities in our laboratory used for ultra-low temperature (below 1 Kelvin) and scanning tunneling microscope studies. It would be used to establish the quality of the samples that would be studied using our dedicated facilities. An example of this would be in work on electrostatic tuning of the SIT in which films are incorporated in a field effect transistor configuration using a mechanically thinned single-crystal strontium titanate (STO) substrate as a gate insulator. The dielectric constant of STO at low temperatures depends upon the electric field, thus the charge transfer is a nonlinear function of gate voltage. The PPMS would be used to calibrate specific substrates before committing them to dilution refrigerator experiments. The instrument will contribute to the training of graduate students in a traditional physics Ph.D. program as well as provide opportunities for undergraduates and high school students to experience research.

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A Physical Properties Measurement System (PPMS) will be used to investigate the quantum properties of highly correlated and disordered materials. Problems under investigation include the superconductor-insulator transition in two dimensions, metal-insulator transitions in oxide film systems, and the nature of superconducting fluctuations in underdoped cuprates. These are important problems in contemporary condensed matter physics. The PPMS would complement a series of dedicated facilities in our laboratory used for ultra-low temperature (below 1 Kelvin) and scanning tunneling microscope studies. It would provide a means of carrying out extensive, electrical transport studies of thin films in magnetic fields of up to 9T, over a temperature range from 1.9K to 400K. These are necessary to establish the quality of the samples that would be studied using our dedicated facilities. The instrument will contribute to the training of graduate students in a traditional physics Ph.D. program as well as provide opportunities for undergraduates and high school students to experience experimental research.

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