eprintid: 1569542
rev_number: 32
eprint_status: archive
userid: 608
dir: disk0/01/56/95/42
datestamp: 2017-10-20 10:11:06
lastmod: 2021-11-01 23:51:30
status_changed: 2017-10-20 10:11:06
type: thesis
metadata_visibility: show
creators_name: Johnson, N
title: Towards Single Electron Interferometry
ispublished: unpub
divisions: UCL
divisions: B04
divisions: C06
divisions: F64
keywords: Experimental quantum mechanics, solid state physics, electronics, electron pump, semiconductor physics
abstract: There have been many studies and suggested technological applications using the two dimensional electron system in the GaAs/AlGaAs heterostructure. These have mostly focused on the behaviour of electrons propagating at or close to the Fermi Energy. More recently, one such application of this two dimensional system is for an electron pump, which isolates electrons from the two dimensional electron gas and pumps them individually at energies typically 100 meV above the Fermi energy, using surface gates to create a dynamic quantum dot. This energy regime had been previously unobtainable. We can utilise the high accuracy output of the pump - consistency that each pumped electron has the same properties, to study fundamental single particle physics, and work towards technological schemes, at this high energy. In this work we set out to continue and extend the previous work in this fi eld. We present new measurements that detail an electron detector barrier that we can use both as a sampling oscilloscope, with a bandwidth approaching 100 GHz, or to measure the wavepacket properties of electrons, including their energy and time of arrival with high resolution. After developing and establishing the electron detector, we detail a series of experiments that utilise it to measure the electron velocity, scattering mechanisms and wavepacket size. We show this work maps consistently to theory, and further, we begin to demonstrate control of the electron wavepacket, with the possibility that this hot electron system could have future technological applications. This is all put together in the construction of an interferometer, which seeks to complete our understanding of electrons in this system by measuring coherence of the wavefunction, a key step to demonstrating construction of a prescribed state.
date: 2017-08-28
date_type: published
oa_status: green
full_text_type: other
thesis_class: doctoral_open
language: eng
thesis_view: UCL_Thesis
primo: open
primo_central: open_green
verified: verified_manual
elements_id: 1411008
lyricists_name: Johnson, Nathan
lyricists_id: NLJOH33
actors_name: Johnson, Nathan
actors_id: NLJOH33
actors_role: owner
full_text_status: public
pages: 141
event_title: UCL
institution: UCL (University College London)
department: Electronic and Electrical Engineering
thesis_type: Doctoral
editors_name: Pepper, M
citation:        Johnson, N;      (2017)    Towards Single Electron Interferometry.                   Doctoral thesis , UCL (University College London).     Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/1569542/7/Johnson_Nathan_Johnson_PhD_final.pdf