SPICE Workshop on Quantum Matter for Quantum Technologies, May 21st - May 23rd 2024
Liam Cohen
Liam A. Cohen,1 , ∗ Noah L. Samuelson,1 , ∗ Will Wang,1 Simon Blanch,1 Michael P. Zaletel,2, 3 and Andrea F. Young1 , †
1Department of Physics, University of California at Santa Barbara, Santa Barbara CA 93106, USA 2Department of Physics, University of California, Berkeley, California 94720, USA 3Material Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA (Dated: May 20, 2024)
Anyons are particles with both fractional charge and fractional exchange statistics that emerge as elemen- tary excitations of fractional quantum Hall phases[1–5]. Experimentally, fractional statistics manifest directly in the edge-state Fabry-Pe ́rot interferometer geometry[6–9], where the presence of Nqp localized anyons in the interferometer bulk contributes a phase Nqpθa to the observed interference pattern, where θa is twice the statistical exchange phase[10]. Similarly, the presence of fractional charges, as well as the non-Fermi liquid behavior of fractional quantum Hall edge modes, may be probed via bias-dependent tunneling experiments at a single quantum point contact. In this talk, I will discuss our direct measurements of θa in a monolayer graphene Fabry-Pe ́rot interferometer at ν = 1/3 as well as our measurements interrogating the consequences of fractional charge at a quantum point heterojunction between quantum Hall states at ν = 1/3 and ν = 1. Our measure- ments have revealed a stunning array of curious properties of these anyons beyond their theoretically expected charge and statistics; these include minutes-long anyon charging dynamics, Andreev-like scattering of fractional quasiparticles, and an impossible electronic device - a D.C. voltage step-up transformer.
∗ These authors contributed equally to this work
† andrea@physics.ucsb.edu
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