Absorption spectroscopy with quantum light: experimental and theoretical simulations based on arbitrary spectral shapes generated with a programable filter

Absorption spectroscopy is a useful technique to detect the presence of specific elements in samples. However, its usefulness can be severely limited in certain frequency bands due to technological limitations, such as the lack of narrowband filters to unveil spectral features, or the lack of highly...

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Detalles Bibliográficos
Autor: Padilla Camargo, Alejandra Araceli
Tipo de recurso: tesis de maestría
Fecha de publicación:2023
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/399085
Acceso en línea:https://hdl.handle.net/2117/399085
Access Level:acceso abierto
Palabra clave:Absorption spectra
Interferometers
Photons
quantum light
frequency-entangled photons
absorption spectroscopy
interferometer
SU(1,1)
Espectre d'absorció
Interferòmetres
Fotons
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Telecomunicació òptica
Descripción
Sumario:Absorption spectroscopy is a useful technique to detect the presence of specific elements in samples. However, its usefulness can be severely limited in certain frequency bands due to technological limitations, such as the lack of narrowband filters to unveil spectral features, or the lack of highly sensitive detectors to detect weak signals. This master?s thesis shows how two specific schemes, that make use of quantum light, can overcome these limitations, allowing the use of a technology developed at one frequency band at a different frequency where this technology is not available. As a first step, instead of samples, we use a programmable optical filter designed for the telecom industry that can generate filters with arbitrary shapes at 1550 nm. The two situations are analogous. In the first scheme, we show experimentally that the spectral shape of filters can be measured by detecting the coincidences between pairs of frequency-entangled photons generated at 1550 nm and 810 nm. We address the limitations of this first scheme and show theoretically that a second scheme, based on the use of SU(1,1) interferometers, allows to do spectroscopic measurements without the need to detect coincidences counts.