Now showing items 1-16 of 16

• #### Atomic quantum metrology with narrowband entangled and squeezed states of light ﻿

(Universitat Politècnica de Catalunya, 2012-06-29)
Doctoral thesis
Open Access
The use of light, especially of laser light, is in many cases the most sensitive way to perform measurements. However, the highest sensitivity that can be achieved with laser light as probe is bounded by the standard quantum ...
• #### Closed-loop control of magnetic fields for atomic physics experiments ﻿

(Universitat Politècnica de Catalunya, 2017-09-08)
Master thesis
Open Access
This project explores the control of magnetic fields through active feedback, ultimately bringing the magnetic field noise level below the required threshold, for one single axis. An absolute stability of less than 400 uG ...
• #### Digital signal processing and control for an optical magnetometer based on zero-field resonance ﻿

(Universitat Politècnica de Catalunya, 2020-09-01)
Master thesis
Restricted access - confidentiality agreement
• #### Entanglement and state characterisation from two-photon interference ﻿

(Universitat Politècnica de Catalunya, 2015-11-03)
Doctoral thesis
Open Access
This thesis analyses the effects of two-photon interference in a polarisation squeezed state under two different points of view: on one hand, it presents a new method to obtain the temporal wavefunction of a state of two ...
• #### High-coherence light source for atom trapping and cooling ﻿

(Universitat Politècnica de Catalunya, 2012-09-06)
Master thesis
Open Access
[ANGLÈS] A master clock (frequency reference) for experiments related to cold and trapped rubidium atoms was developed. From a telecommunication fibre laser source at 1560 nm, frequency-doubling was optimized to obtain an ...
• #### Interaction-based nonlinear quantum metrology with a cold atomic ensemble ﻿

(Universitat Politècnica de Catalunya, 2014-02-07)
Doctoral thesis
Open Access
In this manuscript we present an experimental and theoretical investigation of quantum-noise-limited measurement by nonlinear interferometry, or from another perspective, quantum-noise-limited interaction-based measurement. ...
• #### Narrowband filtering for atom-resonant photon pair generation ﻿

(Universitat Politècnica de Catalunya, 2017-10-27)
Master thesis
Open Access
In this master's thesis we study two filtering techniques, first the Faraday anomalous dispersion optical filter (FADOF) and second a monolithic Fabry-Pérot interferometer with the aim of filtering down-converted photon ...
• #### Optimal signal recovery for pulsed balanced detection ﻿

(Universitat Politècnica de Catalunya, 2015-01-27)
Doctoral thesis
Open Access
To measure quantum features in a classical world constrains us to extend the classical technology to the limit, inventing and discovering new schemes to use the classical devices, while reducing and filtering the sources ...
• #### Precision of cavity-enhanced optical rotation measurements ﻿

(Universitat Politècnica de Catalunya, 2016-07-22)
Master thesis
Open Access
Covenantee:   Institut de Ciències Fotòniques (ICFO)
The signal to noise ratio in atomic magnetometry is fundamentally limited by the optical depth of the atomic ensemble. During the last decade, different technics for optical depth enhancement has been developed by several ...
• #### Quantum control of an ultracold quantum gas ﻿

(Universitat Politècnica de Catalunya, 2019-09-09)
Master thesis
Open Access
This thesis is devoted to the study of quantum control of an ultracold atomic ensemble of $^{87}$Rb. Stroboscopic probing is used to achieve real-time tracking of the collective spin magnitude and orientation via non-destructive ...
• #### Quantum Control of Cold Atoms using microwaves ﻿

(Universitat Politècnica de Catalunya, 2011-09-08)
Master thesis
Open Access
English: We study quantum control of the ground hyperfine manifold of alkali-metal atoms based on applied microwave fields. We performed microwave spectroscopy both in the frequency and the time domain resulting in the ...
• #### Quantum metrology with high-density atomic vapors and squeezed states of light ﻿

(Universitat Politècnica de Catalunya, 2016-10-14)
Doctoral thesis
Open Access
Nowadays there is a considerable progress in optical magnetometry and spin noise spectroscopy, which use magnetically-sensitive atomic ensembles and optical read-out, approaching the limits set by quantum mechanics. In ...
• #### Rubidium resonant squeezed light from a diode-pumped optical-parametric oscillator ﻿

(Universitat Politècnica de Catalunya, 2009-06-30)
Doctoral thesis
Open Access
La luz comprimida (squeezed light) es uno de los componentes importantes de los experimentos de memorias cuánticas. Un almacenamiento eficiente<br/>de la luz comprimida en una colectividad de átomos exige que la luz ...
• #### Saturated absorption frequency locking and second harmonic generation for narrowband entangled photon pair generation ﻿

(Universitat Politècnica de Catalunya, 2016-09-08)
Master thesis
Open Access
The design of two locking systems for light sources desired to generate narrowband photon pairs is under study. First a DBR laser will be locked to the D1 transition frequency of Rb 87 using a Doppler-free Saturated ...
• #### Spontaneous parametric down-conversion sources for generation of atom-resonant quantum light ﻿

(Universitat Politècnica de Catalunya, 2018-03-19)
Doctoral thesis
Open Access
This thesis studies different designs of optical parametric oscillators as sources of atom-resonant quantum light resonant with the rubidium D1 line.We analyze the mode structure and filtering techniques in a conventional ...
• #### Ultranarrow Faraday rotation filter for creating narrowband atom-resonant entangled photon pairs ﻿

(Universitat Politècnica de Catalunya, 2013-07-19)
Master thesis
Open Access
[ANGLÈS] We describe experimental results on a novel optical filter based on the FADOF (Faraday Anomalous Dispersion Optical Filter) principle, and its application to production of atom-resonant entangled photon pairs at ...