Browsing by Contributor "Acín dal Maschio, Antonio"
Now showing items 1-20 of 40
-
Analysis of performance of the Chordal Branch and Bound algorithm
(Universitat Politècnica de Catalunya, 2022-07-07)
Master thesis
Open Access
Covenantee: Universitat de Barcelona / Universitat Autònoma de BarcelonaIn the era of quantum technology, benchmarking classical algorithms is necessary for certifying the results given by the quantum device to the optimization problem that is wanted to solve. Here we analyse a new algorithm ... -
Bell inequalities for device-independent protocols
(Universitat Politècnica de Catalunya, 2019-03-26)
Doctoral thesis
Open AccessThe technological era that we live in is sometimes described as the Information Age. Colossal amounts of data are generated every day and considerable effort is put into creating technologies to process, store and transmit ... -
Bounding Hilbert Space dimension from Temporal Correlations
(Universitat Politècnica de Catalunya, 2009-09-09)
Master thesis
Open AccessIn this work, we tackle the problem of assessing the Hilbert space dimension from the set of correlations obtained when measuring in a nonlocal black box scheme. The concept of a dimension witness and its recent applications ... -
Certification of many-body systems
(Universitat Politècnica de Catalunya, 2019-05-17)
Doctoral thesis
Open AccessQuantum physics is arguably both the most successful and the most counterintuitive physical theory of all times. Its extremely accurate predictions on the behaviour of microscopic particles have led to unprecedented ... -
Characterizing and witnessing multipartite correlations : from nonlocality to contextuality
(Universitat Politècnica de Catalunya, 2014-02-10)
Doctoral thesis
Open AccessIn the past century, experimental discoveries have witnessed phenomena in Nature which challenge our everyday classical intuition. In order to explain these facts, quantum theory was developed, which so far has been able ... -
Classical simulation of restricted quantum computations
(Universitat Politècnica de Catalunya, 2013-09-09)
Master thesis
Open Access[ANGLÈS] We study restricted models of measurement-based quantum computation; and we investigate whether their output probability distributions can be sampled from efficiently on a classical computer. We find that even for ... -
Detection of nonlocality with two-body correlation functions
(Universitat Politècnica de Catalunya, 2015-09-10)
Master thesis
Open AccessNonlocality detection in multipartite quantum systems is of great interest. The most popular tool to detect nonlocality in quantum systems are Bell inequalities. Most of the provided constructions of multipartite Bell ... -
Device-independent certification of quantum resources
(Universitat Politècnica de Catalunya, 2018-09-19)
Doctoral thesis
Open AccessThe last two decades have been a very fruitful period for the fundamental research related to quantum information theory. Today we have a fairly good understanding of how intrinsically quantum properties affect various ... -
Device-independent information protocols: measuring dimensionality, randomness and nonlocality
(Universitat Politècnica de Catalunya, 2013-02-22)
Doctoral thesis
Open AccessThe device-independent formalism is a set of tools to analyze experimental data and infer properties about systems, while avoiding almost any assumption about the functioning of devices. It has found applications both in ... -
Entanglement and non local correlations: quantum resources for information processing
(Universitat Politècnica de Catalunya, 2013-01-18)
Doctoral thesis
Open AccessQuantum Information Theory (QIT) studies how information can be processed and transmitted when encoded on quantum states. Practically, it can be understood as the effort to generalize Classical Information Theory to the ... -
Entanglement and non-locality of pure quantum states.
(Universitat Politècnica de Catalunya, 2010-07-19)
Master thesis
Open AccessWe study the process of majorisation and interconversion of bipartite states, and apply the formalism for analysing the local and non-local content of pure bipartite entangled states. We proved that the states which are ... -
Entanglement in the graph-state formalism
(Universitat Politècnica de Catalunya, 2009-09-09)
Master thesis
Open AccessWe investigate the decoherence dynamics of a class of multi-particle entangled states - graph states - when subjected to individual noise processes. Recent analytical results for Pauli noise channels are summarized here. ... -
Experimental tools for quantum networking operations with single photons and sinlge ions
(Universitat Politècnica de Catalunya, 2014-01-29)
Doctoral thesis
Open AccessOne promising approach for future quantum networks is the combination of strings of trapped ions as quantum-information processors with entangled photon pairs produced by spontaneous parametric down conversion (SPDC) to ... -
Exploring nonlocal correlations in many-body systems
(Universitat Politècnica de Catalunya, 2018-07-19)
Master thesis
Open AccessWe address the question of how to evaluate the Bell correlations depth, i.e. the number of parties sharing genuinely nonlocal correlations in a multipartite system. Previous work has shown that it is possible to construct ... -
From quantum foundations to quantum information protocols and back
(Universitat Politècnica de Catalunya, 2015-09-23)
Doctoral thesis
Open AccessPhysics has two main ambitions: to predict and to understand. Indeed, physics aims for the prediction of all natural phenomena. Prediction entails modeling the correlation between an action, the input, and what is subsequently ... -
Hierarchical representations in machine learning and many-body quantum physics
(Universitat Politècnica de Catalunya, 2017-10-27)
Master thesis
Open AccessOver the past few years a number of proofs have emerged revealing the many connections between the methods used in quantum-many body physics and those in machine learning. In particular, much attention has been given to ... -
Impact of imperfections on correlation-based quantum information protocols
(Universitat Politècnica de Catalunya, 2016-05-30)
Doctoral thesis
Open AccessQuantum information science is a rapidly evolving field both from the theoretical and the experimental viewpoint, motivated by the fact that protocols exploiting quantum resources can perform tasks that are unfeasible in ... -
Information-theoretical Secret-key agreement and Bound information
(Universitat Politècnica de Catalunya, 2009-02-25)
Master thesis
Open AccessOne big problem of the communication between two parties is the secrecy. That means how much information a third party can obtain by intercepting the messages transmitted from one honest party to the other one. Therefore ... -
Intrinsic randomness in non-local theories: quantification and amplification
(Universitat Politècnica de Catalunya, 2013-06-12)
Doctoral thesis
Open AccessQuantum mechanics was developed as a response to the inadequacy of classical physics in explaining certain physical phenomena. While it has proved immensely successful, it also presents several features that severely ... -
Investigating quantum many-body systems with tensor networks, machine learning and quantum computers
(Universitat Politècnica de Catalunya, 2022-10-14)
Doctoral thesis
Open Access(English) We perform quantum simulation on classical and quantum computers and set up a machine learning framework in which we can map out phase diagrams of known and unknown quantum many-body systems in an unsupervised ...
