IQIM Postdoctoral and Graduate Student Seminar

Friday May 22, 2015 4:00 PM

Engineering Quantum Matter: From Superfluids to Low-Dimensional Electrons

Speaker: Johannes Pollanen, Eisenstein Group, Caltech
Location: East Bridge 114

Abstract: Creating and controlling novel quantum states of matter is at the forefront of modern condensed matter physics. I will discuss two examples of this "create and control" paradigm from my experiences. First, I will describe how we have utilized anisotropic disorder, in the form of high porosity aerogel, to create new chiral superfluid states of 3He. The understanding of these states has broad implications regarding the stability of chiral superconductivity in other compounds, such as Sr2RuO4. In the second part of my talk I will discuss a new device architecture that allows for in situ tunability of the electron density in two-dimensional electron systems (2DES) in gallium-arsenide (GaAs). At high magnetic fields and low temperatures, Coulomb interactions in two dimensions lead to a wide variety of collective electron states including fractional quantum Hall fluids, nematic liquid crystals and exotic solids composed of multi-electron bubbles. Our variable density device provides us with the ability to control the Coulomb interactions responsible for such ground states. Finally, I will remark on how the lessons learned from studying superfluid 3He and 2DES can be harnessed to develop hybrid quantum systems composed of free electrons floating on the surface of liquid helium coupled to nanoscale structures or topological states of matter. These systems provide a unique platform for studying the fundamental physics of low dimensional quantum systems and their potential quantum computing applications.

 

Series IQIM Postdoctoral and Graduate Student Seminar Series

Contact: Marcia Brown at 626-395-4013 marciab@caltech.edu