Advanced measurements for quantum photonics and quantum technologies

<p>Measurements on states of light underpins the entire fields of classical and quantum optics. Without measurement we are unable to gain any information about the light we are studying or about the processes it has undergone. The property of the density matrix of light prior to measurement th...

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Bibliographic Details
Main Author: Phillips, DS
Other Authors: Walmsley, IA
Format: Thesis
Language:English
Published: 2020
Subjects:
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author Phillips, DS
author2 Walmsley, IA
author_facet Walmsley, IA
Phillips, DS
author_sort Phillips, DS
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description <p>Measurements on states of light underpins the entire fields of classical and quantum optics. Without measurement we are unable to gain any information about the light we are studying or about the processes it has undergone. The property of the density matrix of light prior to measurement that we want to measure also relies heavily on the measurement technique we employ. We can use a single-photon detector to measure the particle nature of light--the photon--the discrete quanta of the electromagnetic field. We can conversely measure the wave nature of the light field by making phase-sensitive measurements. In this thesis, we shall explore some advanced implementations and applications of these measurement schemes.</p> <p>First, we shall focus on a specific type of single-photon detector: the Superconducting-Nanowire Single-Photon Detector. We will first consider the integration of these detectors on optical waveguides, and discuss their optical characterisation. Then we will consider a practical application of these detectors by investigating a method to perform broadband spectroscopy with a single detector.</p> <p>We shall then progress to phase-sensitive measurements, and consider the intermediate regime between measuring the wave-like and particle-like nature of light. First we will perform a fundamental investigation of the transition between both measurement regimes. We will see how varying the phase reference itself allows us to tune between both regimes. Following this we will discuss an application of this intermediate regime, by considering an experimental setup to perform state tomography with a weak phase reference.</p> <p>The final consideration of this thesis will be a theoretical benchmarking scheme for a practical application of quantum optics. The manipulation of certain quantum states of light followed by a photon-number measurement can have practical applications in a variety of fields, and therefore validating the results is of extreme importance. On this final topic, we will discuss an experimentally friendly technique to benchmark the output of such measurements by considering smaller subsystems, and the practical requirements of this technique.</p>
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spelling oxford-uuid:9b30d6e9-ad19-4c2c-a0f1-1b04521b38f92022-03-27T00:26:58ZAdvanced measurements for quantum photonics and quantum technologiesThesishttp://purl.org/coar/resource_type/c_db06uuid:9b30d6e9-ad19-4c2c-a0f1-1b04521b38f9Quantum opticsEnglishHyrax Deposit2020Phillips, DSWalmsley, IA<p>Measurements on states of light underpins the entire fields of classical and quantum optics. Without measurement we are unable to gain any information about the light we are studying or about the processes it has undergone. The property of the density matrix of light prior to measurement that we want to measure also relies heavily on the measurement technique we employ. We can use a single-photon detector to measure the particle nature of light--the photon--the discrete quanta of the electromagnetic field. We can conversely measure the wave nature of the light field by making phase-sensitive measurements. In this thesis, we shall explore some advanced implementations and applications of these measurement schemes.</p> <p>First, we shall focus on a specific type of single-photon detector: the Superconducting-Nanowire Single-Photon Detector. We will first consider the integration of these detectors on optical waveguides, and discuss their optical characterisation. Then we will consider a practical application of these detectors by investigating a method to perform broadband spectroscopy with a single detector.</p> <p>We shall then progress to phase-sensitive measurements, and consider the intermediate regime between measuring the wave-like and particle-like nature of light. First we will perform a fundamental investigation of the transition between both measurement regimes. We will see how varying the phase reference itself allows us to tune between both regimes. Following this we will discuss an application of this intermediate regime, by considering an experimental setup to perform state tomography with a weak phase reference.</p> <p>The final consideration of this thesis will be a theoretical benchmarking scheme for a practical application of quantum optics. The manipulation of certain quantum states of light followed by a photon-number measurement can have practical applications in a variety of fields, and therefore validating the results is of extreme importance. On this final topic, we will discuss an experimentally friendly technique to benchmark the output of such measurements by considering smaller subsystems, and the practical requirements of this technique.</p>
spellingShingle Quantum optics
Phillips, DS
Advanced measurements for quantum photonics and quantum technologies
title Advanced measurements for quantum photonics and quantum technologies
title_full Advanced measurements for quantum photonics and quantum technologies
title_fullStr Advanced measurements for quantum photonics and quantum technologies
title_full_unstemmed Advanced measurements for quantum photonics and quantum technologies
title_short Advanced measurements for quantum photonics and quantum technologies
title_sort advanced measurements for quantum photonics and quantum technologies
topic Quantum optics
work_keys_str_mv AT phillipsds advancedmeasurementsforquantumphotonicsandquantumtechnologies