Type
Text
Type
Dissertation
Advisor
Ismail Zahed | Rafailovich, Miriam H. | Sokolov, Jonathan | Meigan Aronson | Serge Luryi.
Date
2010-05-01
Keywords
Physics, Condensed Matter | Aharonov-Bohm oscillation, electron Fabry-Perot interferometers, fractional quantum Hall effect, fractional statistics, interference of e/3 quasiparticles encircling 2/5 FQH fluid, quantum transport
Department
Department of Physics
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/72570
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
This dissertation describes quantum Hall transport experiments on Fabry-Perot electron interferometers fabricated from GaAs/AlGaAs heterostructure material. The devices consist of an island separated from the two-dimensional (2D) electron bulk via two tunable constrictions. Front gates deposited in etch trenches permit to fine tune the device. When tunneling occurs in the constrictions, electrons perform closed orbits around the island, producing an Aharonov-Bohm oscillatory signal in the conductance. Quantized plateaus in longitudinal and Hall resistances of the device allow us to determine the Landau level filling in both the bulk and the constriction.A comprehensive experimental characterization of quantum Hall and Shubnikovde Haas (SdH) transport is presented in the first interferometer. Application of front-gate voltage affects the constriction electron density, but the 2D bulk density remains unaffected. Analyzing the data within a Fock-Darwin model, we obtain the front-gate bias dependencies of constriction electron density, and, extrapolating to zero magnetic field, the number of 1D electric subbands resulting from the electron confinement in the constrictions.In the same interferometer, by carefully tuning the constriction front gates, we find a regime where interference oscillations with period h/2e persist throughout the transition between the integer quantum Hall plateaus 2 and 3, including half-filling. In our experiment, neither period nor amplitude of the oscillations show a discontinuity at half-filling, indicating that only one interference path exists throughout the transition.In the second interferometer, etch trench depletion is such that in the fractional quantum Hall (FQH) regime, filling 1/3 current-carrying chiral edge channels pass through the constrictions and encircle an island of the 2/5 FQH fluid. In this regime, we observe magnetic flux and charge periods 5h/e and 2e, respectively, corresponding to creation of ten e/5 Laughlin quasiparticles in the island. The observed experimental periods are interpreted as imposed by the anyonic statistical interaction of fractionally charged quasiparticles.
Recommended Citation
LIN, PING, "Quantum Transport in Electron Fabry-Perot Interferometers in Quantum Hall Regime" (2010). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 1774.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/1774