CAREER: Heat Capacity Study on Low Dimensional Electronic Systems at Low Temperature

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

This CAREER project addresses simultaneous heat capacity and transport measurements on Kosterlitz-Thouless (KT) type superconducting transitions and Superconductor-Insulator Transi-tions (SIT) at temperatures down to ~10mK. The project includes design and fabrication of a state-of-the-art low temperature nano-calorimeter. With a SQUID readout, the expected sensitiv-ity of the calorimeter is expected to be sufficient to detect the electronic heat capacity contribu-tion from a metal (copper, for example) of ~1 nanogram at 10mK, corresponding to a monolayer film covering an area of ~1mm in diameter. Superconducting transitions of ultrathin AuIn, Ta, and Bi films will be investigated in a continuous flow He cryostat, and a dilution refrigerator. Experimental techniques to be developed are expected to also impact the study of thermody-namic properties of other 2D systems such as Fermi liquids, Kondo systems, and electrons in semiconductor interfaces, providing a foundation for a lifetime of contribution and education in this field. The project involves education and training of undergraduate and graduate students in industry-standard microfabrication techniques and a variety of condensed matter techniques. Computer-based acquisition and analysis of large data sets requires training at the frontier of information technology. These opportunities will help students develop future-oriented perspectives on sci-ence and technology. The PI will develop a new course to teach principles and applications of various state-of-the-art devices to science majors and graduate students from various disciplines of science. The course will offer students active participation in the class activity in the form of case study, literature search, and poster presentations. An outreach effort includes creating a comprehensive website containing educational materials related with research and educational activities, K12 and community college lectures, demonstration, and laboratory tours. ***