Strain to spectra

: simulations of strain, NMR spectra and quantum memories in InGaAs quantum dots

Abstract

Quantum dots have the potential to play a key role in emerging quantum technologies. Their proposed uses range from sources of single or entangled photons needed for quantum communication and photonic quantum computation, to as long term quantum memories in which qubits can be stored for later use. Understanding and characterising the properties of quantum dots is therefore of vital importance. In this thesis we investigate the impact of recent measurements of the gradient elastic tensor - a fundamental part of the strain environment of an InGaAs quantum dot, have on the properties of such a structure. We will show how the quadrupolar interaction is modified by such re-calibration, and assess the impact such changes may have for the possible applications of quantum dots. We will then investigate the advantages that more symmetrical quantum dots may possess, both in terms of nuclear quadrupolar variation and in the resulting coherence time of a trapped electron. Our work is largely computational, with some distinct advantages in run time and ease of use as compared to other simulation methods. Some simple theoretical models are discussed to aid intuitive understanding.

Date of Award	27 Sept 2022
Original language	English
Awarding Institution	University of Bristol
Supervisor	John G Rarity (Supervisor), Ruth Oulton (Supervisor) & Dara P S McCutcheon (Supervisor)