Eun-Ah Kim
Department of Physics
Stanford University

Title: "In search of fractional statistics: Anyon there?"

Abstract:
Quasiparticles of fractional quantum Hall (FQH) fluids are predicted to be finite energy vortices carrying fractional charge and fractional statistics. These properties reflect the non-trivial topological order which characterizes each FQH state as a distinct phase. However, strong evidence for fractional statistics has remained an open experimental challenge. I will first discuss a three-terminal “T-junction” as an experimental setup for directly detecting fractional charge and statistics of fractional quantum Hall quasiparticles via cross current noise measurements. I will show that the cross current correlation (noise) can be written in a simple form with all the statistics dependence captured in a factor of cos\theta in one of two contributions, where the statistical angle theta is defined by the phase gained by a two quasiparticle wave function upon exchange. We also predicted that the vortices of Laughlin states exhibit a “bunching” effect, while higher states in the Jain sequences exhibit an “anti-bunching” effect. Secondly, I will discuss a quantum Hall interferometer motivated by the recent experiments by F.E.Camino, W. Zhou and V.J. Goldman. I will consider the conductance oscillations that result from the incompressibility of the FQH liquid occupying the island and the interference condition for the quasiparticles encircling the outer ring. I will present a perturbative calculation of the temperature dependence of the amplitude of the oscillation and compare the result with the experiment.