Disorder Induced Novel Quantum Phases in Superfluid 3He

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****NON-TECHNICAL ABSTRACT****The physics of disorder is integrated in an extremely large area of science as a common thread, and the impact of research on this subject permeates from the highly practical to the purely academic. This project addresses a fundamental question: ?How does the nature of a quantum matter evolve in response to disorder?? Unlike other physical systems, the liquid state of 3He at low temperatures is a unique, practically disorder free system for which we have a quantitative understanding. Furthermore, the superfluid phases of 3He, which can be characterized more generally as unconventional superconductivity, are known to exhibit extreme sensitivity to external disorder. This project will investigate the effect of controlled disorder on this unique quantum state of matter. The effect of two distinct forms of disorder: anisotropic disorder in high porosity aerogel and surface disorder in thin films of liquid will be studied. The ultimate goal of the project is to identify novel, disorder-induced quantum phases which have been predicted to emerge in these systems. The research will be conducted by two teams of graduate and undergraduate students. Undergraduate research is an important element of education and also an effective way of retaining Physics undergraduate students in this field. The PI of the project will continue to interact with local science teachers and students through lectures/demonstrations and participation in science fairs. ****TECHNICAL ABSTRACT****This project will investigate the superfluid phases of 3He in the presence of controlled disorder presented by high porosity aerogel and by confinement in the form of films. The ultimate goal of the proposed project is to identify disorder-induced novel quantum phases which have been predicted to emerge in these systems. The effect of anisotropic disorder on anisotropic superfluid can be studied in a systematic way in uniaxially deformed aerogel. The 1D-like polar phase is predicted to be stabilized due to anisotropic disorder induced in stretched aerogel. Experiments will be performed to elucidate the effect of surface disorder on superfluid 3He employing state-of-the-art microelectro-mechanical systems (MEMS) to form controlled films and to detect various phase transition features. This project will focus on quasi-two dimensional films where the re-entrant behavior of the A-B transition and the emergence of an inhomogeneous superfluid phase have been theoretically predicted. The proposed research will be conducted by two teams of graduate and undergraduate students. Retaining Physics undergraduate students is as important as increasing their number. One effective way is undoubtedly through undergraduate research.