Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Optical Quantum Information: New States, Gates and Algorithms

B. P. Lanyon

Published Feb 1, 2009• 0 citations
OpenAlex

Abstract

Mandatory declaration by the author This thesis is composed of my original work, and contains no material previously pub-lished or written by another person except where due reference has been made in the text. I have clearly stated the contribution by others to jointly-authored works that I have included in my thesis. I have clearly stated the contribution of others to my thesis as a whole, including statistical assistance, survey design, data analysis, significant tech-nical procedures, professional editorial advice, and any other original research work used or reported in my thesis. The content of my thesis is the result of work I have carried out since the commencement of my research higher degree candidature and does not include a substantial part of work that has been submitted to qualify for the award of any other degree or diploma in any university or other tertiary institution. I have clearly stated which parts of my thesis, if any, have been submitted to qualify for another award. I acknowledge that an electronic copy of my thesis must be lodged with the University Library and, subject to the General Award Rules of The University of Queensland, im-mediately made available for research and study in accordance with the Copyright Act 1968. I acknowledge that copyright of all material contained in my thesis resides with the copyright holder(s) of that material. Statement of contributions to jointly authored works contained in the thesis. This thesis presents six jointly authored works that have been published by, or submitted to, peer-reviews scientific journals. Each is presented as a Chapter in this thesis. Follow-ing each is a detailed contribution statement. Statement of contributions by others to the thesis as a whole. No contributions by others.

Related papers

Techniques for Quantum Computing State Generation, Discrete Logarithms in Elliptic Curve Groups, Reliable Global Control Schemes and Algorithmic Cooling

Phillip Kaye

I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final revisions, as accepted by my examiners. I understand that my thesis may be made electronically available to the public.

•Jan 1, 2007•0 citations

Smooth inductively coupled ring trap for cold atom optics

Aline N. Dinkelaker

This thesis is the result of the author’s original research. It has been composed by the author and has not been previously submitted for examination which has led to the award of a degree. The copyright of this thesis belongs to the author under the terms of the United Kingdom Copyright Acts as qualified by University of Strathclyde Regu-lation 3.50. Due acknowledgement must always be made of the use of any material contained in, or derived from, this thesis. Signed:

•Jan 1, 2013•0 citations

Open quantum systems and applications to the quantum information theory

Theodora Kolioni

Η επιστήμη της κβαντικής πληροφορίας επιδιώκει την κατανόηση, στο ευρύτερο πλαίσιο της Κβαντομηχανικής, της πληροφορίας ως φυσικό αλλά και ως μαθηματικό εργαλείο. Έτσι, η κατανόηση των ιδιοτήτων της κβαντικής πληροφορίας (όπως π.χ. του εναγκαλισμού), κρίνεται απαραίτητη προϋπόθεση για την ανάπτυξη νέων κβαντικών τεχνολογιών. Στο πλαίσιο της διδακτορικής μου έρευνας ασχολήθηκα με α). την πλήρη κατανόηση και την περιγραφή της επικοινωνίας μεταξύ των απομακρυσμένων κβαντικών συστημάτων που αλληλεπιδρούν μέσω ενός κβαντικού πεδίου και β). την κατασκευή ενός θεωρητικού μοντέλου για την ακριβή περιγραφή του φαινομένου της μετάδοσης της πληροφορίας, η οποία δεν οδηγεί σε παραβίαση της αιτιότητας (Einstein causality). Για το σκοπό αυτό, στην παρούσα διατριβή μελετήθηκε το σύστημα των δύο εντοπισμένων ανιχνευτών (αρμονικών ταλαντωτών) που αλληλεπιδρούν μέσω ενός άμαζου βαθμωτού κβαντικού πεδίου, στην κατάσταση του κενού, μέσω μίας Unruh-DeWitt αλληλεπίδρασης. Το σύστημα αυτό είναι ισοδύναμο με ένα ανοικτό κβαντικό σύστημα (QBM model), όπου το πεδίο παίζει το ρόλο του περιβάλλοντος. Είναι ακριβώς επιλύσιμο και αποτελεί ένα μοντέλο κατάλληλο για την αντιμετώπιση θεμελιωδών προβλημάτων που αφορούν στις αλληλεπιδράσεις μεταξύ σωματιδίων και πεδίου, όπως το πρόβλημα της αιτιότητας (causality) και της τοπικότητας (locality) στις μετρήσεις κβαντικού πεδίου (quantum field measurements) που σχετίζονται και με τα πρόσφατα προτεινόμενα κβαντικά πειράματα στο διάστημα. Η ανάλυση της ακριβούς λύσης της χρονικής εξέλιξης του μοντέλου μας, οδήγησε στα ακόλουθα αποτελέσματα. i). Κοινές προσεγγίσεις που χρησιμοποιούνται για την μελέτη αντίστοιχων ανοικτών κβαντικών συστημάτων αποτυγχάνουν όταν η απόσταση μεταξύ των ανιχνευτών (συστημάτων) γίνεται ίση με την τάξη μεγέθους του χρόνου αποσύνθεσης (relaxation time) του συστήματος. Συγκεκριμένα, η μελέτη της δημιουργίας των συσχετισμών μεταξύ των απομακρυσμένων ανιχνευτών (συστημάτων) δεν περιγράφεται καλά από τη συνηθισμένη θεωρία διαταραχών (θεωρία διαταραχών 2ης τάξης) και την προσέγγιση Markov. ii). Υπάρχει μια μοναδική ασυμπτωτική κατάσταση στην οποία καταλήγει το υπό μελέτη σύστημα, η οποία είναι κατάσταση συσχετισμού (correlated state), όχι όμως κατάσταση εναγκαλισμού (entangled state), εκτός και αν η απόσταση μεταξύ των ανιχνευτών είναι τάξης μεγέθους του μήκους κύματος του ανταλλασσόμενου μεταξύ τους, κβάντου. iii). Τέλος, διαπιστώθηκε ότι η εξέλιξη των φαινομενικά εντοπισμένων παρατηρήσιμων μεγεθών είναι μη-αιτιακή. Το τελευταίο είναι μια σημαντική επίδειξη του προβλήματος των δύο ατόμων του Fermi, σε ένα σύστημα που μπορεί να επιλυθεί με ακρίβεια. Υποστηρίζουμε ότι η έννοια του εναγκαλισμού στα σχετικιστικά συστήματα, και ειδικότερα η μελέτη της φυσικής σημασίας της εξαγωγής του εναγκαλισμού από το κενό (Harvesting) απαιτεί επανακαθορισμό λόγω του προβλήματος της αιτιότητας. Το αποτέλεσμα της έρευνας αυτής, αναμένεται να συμβάλλει στην ανάπτυξη του τομέα της κβαντικής πληροφορίας, μέσα από τα αποτελέσματα που αφορούν στην κατανόηση της κβαντικής επικοινωνίαςσε μεγάλες αποστάσεις.

•Oct 1, 2019•0 citations

Development of encoding and entanglement for free space quantum key distribution.

Yaseera Ismail

It is established that the manipulation of quantum information is bound only by the laws of physics and thus information can be characterised, quantified and processed as a physical entity using the basic properties of quantum mechanics.The most advanced quantum information related technology at present is Quantum Key Distribution (QKD).QKD encodes information into a quantum data carrier, in particular, a single photon that is transported through a quantum channel to produce secure key.To date QKD has been demonstrated across two types of channels which is generally fibre or free space.Free space QKD is beneficial since it provides various mediums for the encoding.When considering the atmosphere as a medium for free space QKD, one of the challenges is the effects of turbulence.Apart from the turbulence effects, one of the other challenges faced with implementing a QKD system, is the use of an appropriate source of single photons for the encoding.A good implementation of a source of single photons would be to make use of entanglement.This thesis addresses the above two aspects of QKD Development of Encoding and Entanglement for Free Space Quantum Key Distribution DECLARATION 1 -PLAGIARISM I, Yaseera Ismail, declare that 1.The research reported in this thesis, except where otherwise indicated, is my original research.2. This thesis has not been submitted for any degree or examination at any other university.3. This thesis does not contain other persons' data, pictures, graphs or other information, unless specifically acknowledged as being sourced from other persons.4. This thesis does not contain other persons writing, unless specifically acknowledged as being sourced from other researchers.Where other written sources have been quoted, then:(a) Their words have been re-written but the general information attributed to them has been referenced (b) Where their exact words have been used, then their writing has been placed in italics and inside quotation marks, and referenced.5. This thesis does not contain text, graphics or tables copied and pasted from the Internet, unless specifically acknowledged, and the source being detailed in the thesis and in the References sections.

•May 12, 2016•0 citations

Measuring the Quantum State of Light

Ulf Leonhardt

This is a well written book; it makes easy and pleasant reading for both experts and physicists working in other areas. The book is almost self-contained. It comprises six chapters. In the first three the author introduces the subject and deals with basic results and analytic tools from quantum optics: quantum theory of light and quasi-probability functions. In the fourth chapter he discusses the quantum-mechanical description of simple optical instruments. The last two chapters are the core of the book; they are devoted to a discussion of quantum tomography, joint measurement of position and momentum and the quantum-optical phase. The author was directly involved in the development of the field, which guarantees a fresh and clear exposition. At the same time he makes an open effort for a general (re)formulation of the subject and to present the `classic' solutions to a number of problems in the area. Overall, the presentation of quantum tomography is shaped by a personal view but it accounts sufficiently for the different approaches discussed in the literature. My only reservation is the way in which connections between classical and quantum tomography are presented. In particular, I find that an explicit statement that classical tomography (inverse Radon transform) cannot be straightforwardly applied to the quantum case should be made. The book was published in 1997. Since then the field has been growing rapidly and impetuously and the book shows its age. Nevertheless, it is still a useful reference tool for active researchers and a nice and valuable introduction for (graduate) students who are entering this area. It is worth noting that only a few books have been published on this subject; Leonhardt's volume is well written and to the point. The book is dedicated to Harry Paul, the supervisor of Leonhardt's postdoctoral thesis and the coauthor of most of his papers in the area. M G A Paris

Measurement Science and Technology•Nov 20, 2000•28 citations

Students' understanding of quantum phenomena

Gren Ireson

Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.

•Jan 1, 2000•0 citations
Mandatory declaration by the author This thesis is composed of my original work, and contains no material previously pub-lished or written by another person except where due reference has been made in the text. I have clearly stated the contribution by others to jointly-authored works that I have included in my thesis. I have clearly stated the contribution of others to my thesis as a whole, including statistical assistance, survey design, data analysis, significant tech-nical procedures, professional editorial advice, and any other original research work used or reported in my thesis. The content of my thesis is the result of work I have carried out since the commencement of my research higher degree candidature and does not include a substantial part of work that has been submitted to qualify for the award of any other degree or diploma in any university or other tertiary institution. I have clearly stated which parts of my thesis, if any, have been submitted to qualify for another award. I acknowledge that an electronic copy of my thesis must be lodged with the University Library and, subject to the General Award Rules of The University of Queensland, im-mediately made available for research and study in accordance with the Copyright Act 1968. I acknowledge that copyright of all material contained in my thesis resides with the copyright holder(s) of that material. Statement of contributions to jointly authored works contained in the thesis. This thesis presents six jointly authored works that have been published by, or submitted to, peer-reviews scientific journals. Each is presented as a Chapter in this thesis. Follow-ing each is a detailed contribution statement. Statement of contributions by others to the thesis as a whole. No contributions by others.
Η επιστήμη της κβαντικής πληροφορίας επιδιώκει την κατανόηση, στο ευρύτερο πλαίσιο της Κβαντομηχανικής, της πληροφορίας ως φυσικό αλλά και ως μαθηματικό εργαλείο. Έτσι, η κατανόηση των ιδιοτήτων της κβαντικής πληροφορίας (όπως π.χ. του εναγκαλισμού), κρίνεται απαραίτητη προϋπόθεση για την ανάπτυξη νέων κβαντικών τεχνολογιών. Στο πλαίσιο της διδακτορικής μου έρευνας ασχολήθηκα με α). την πλήρη κατανόηση και την περιγραφή της επικοινωνίας μεταξύ των απομακρυσμένων κβαντικών συστημάτων που αλληλεπιδρούν μέσω ενός κβαντικού πεδίου και β). την κατασκευή ενός θεωρητικού μοντέλου για την ακριβή περιγραφή του φαινομένου της μετάδοσης της πληροφορίας, η οποία δεν οδηγεί σε παραβίαση της αιτιότητας (Einstein causality). Για το σκοπό αυτό, στην παρούσα διατριβή μελετήθηκε το σύστημα των δύο εντοπισμένων ανιχνευτών (αρμονικών ταλαντωτών) που αλληλεπιδρούν μέσω ενός άμαζου βαθμωτού κβαντικού πεδίου, στην κατάσταση του κενού, μέσω μίας Unruh-DeWitt αλληλεπίδρασης. Το σύστημα αυτό είναι ισοδύναμο με ένα ανοικτό κβαντικό σύστημα (QBM model), όπου το πεδίο παίζει το ρόλο του περιβάλλοντος. Είναι ακριβώς επιλύσιμο και αποτελεί ένα μοντέλο κατάλληλο για την αντιμετώπιση θεμελιωδών προβλημάτων που αφορούν στις αλληλεπιδράσεις μεταξύ σωματιδίων και πεδίου, όπως το πρόβλημα της αιτιότητας (causality) και της τοπικότητας (locality) στις μετρήσεις κβαντικού πεδίου (quantum field measurements) που σχετίζονται και με τα πρόσφατα προτεινόμενα κβαντικά πειράματα στο διάστημα. Η ανάλυση της ακριβούς λύσης της χρονικής εξέλιξης του μοντέλου μας, οδήγησε στα ακόλουθα αποτελέσματα. i). Κοινές προσεγγίσεις που χρησιμοποιούνται για την μελέτη αντίστοιχων ανοικτών κβαντικών συστημάτων αποτυγχάνουν όταν η απόσταση μεταξύ των ανιχνευτών (συστημάτων) γίνεται ίση με την τάξη μεγέθους του χρόνου αποσύνθεσης (relaxation time) του συστήματος. Συγκεκριμένα, η μελέτη της δημιουργίας των συσχετισμών μεταξύ των απομακρυσμένων ανιχνευτών (συστημάτων) δεν περιγράφεται καλά από τη συνηθισμένη θεωρία διαταραχών (θεωρία διαταραχών 2ης τάξης) και την προσέγγιση Markov. ii). Υπάρχει μια μοναδική ασυμπτωτική κατάσταση στην οποία καταλήγει το υπό μελέτη σύστημα, η οποία είναι κατάσταση συσχετισμού (correlated state), όχι όμως κατάσταση εναγκαλισμού (entangled state), εκτός και αν η απόσταση μεταξύ των ανιχνευτών είναι τάξης μεγέθους του μήκους κύματος του ανταλλασσόμενου μεταξύ τους, κβάντου. iii). Τέλος, διαπιστώθηκε ότι η εξέλιξη των φαινομενικά εντοπισμένων παρατηρήσιμων μεγεθών είναι μη-αιτιακή. Το τελευταίο είναι μια σημαντική επίδειξη του προβλήματος των δύο ατόμων του Fermi, σε ένα σύστημα που μπορεί να επιλυθεί με ακρίβεια. Υποστηρίζουμε ότι η έννοια του εναγκαλισμού στα σχετικιστικά συστήματα, και ειδικότερα η μελέτη της φυσικής σημασίας της εξαγωγής του εναγκαλισμού από το κενό (Harvesting) απαιτεί επανακαθορισμό λόγω του προβλήματος της αιτιότητας. Το αποτέλεσμα της έρευνας αυτής, αναμένεται να συμβάλλει στην ανάπτυξη του τομέα της κβαντικής πληροφορίας, μέσα από τα αποτελέσματα που αφορούν στην κατανόηση της κβαντικής επικοινωνίαςσε μεγάλες αποστάσεις.
It is established that the manipulation of quantum information is bound only by the laws of physics and thus information can be characterised, quantified and processed as a physical entity using the basic properties of quantum mechanics.The most advanced quantum information related technology at present is Quantum Key Distribution (QKD).QKD encodes information into a quantum data carrier, in particular, a single photon that is transported through a quantum channel to produce secure key.To date QKD has been demonstrated across two types of channels which is generally fibre or free space.Free space QKD is beneficial since it provides various mediums for the encoding.When considering the atmosphere as a medium for free space QKD, one of the challenges is the effects of turbulence.Apart from the turbulence effects, one of the other challenges faced with implementing a QKD system, is the use of an appropriate source of single photons for the encoding.A good implementation of a source of single photons would be to make use of entanglement.This thesis addresses the above two aspects of QKD Development of Encoding and Entanglement for Free Space Quantum Key Distribution DECLARATION 1 -PLAGIARISM I, Yaseera Ismail, declare that 1.The research reported in this thesis, except where otherwise indicated, is my original research.2. This thesis has not been submitted for any degree or examination at any other university.3. This thesis does not contain other persons' data, pictures, graphs or other information, unless specifically acknowledged as being sourced from other persons.4. This thesis does not contain other persons writing, unless specifically acknowledged as being sourced from other researchers.Where other written sources have been quoted, then:(a) Their words have been re-written but the general information attributed to them has been referenced (b) Where their exact words have been used, then their writing has been placed in italics and inside quotation marks, and referenced.5. This thesis does not contain text, graphics or tables copied and pasted from the Internet, unless specifically acknowledged, and the source being detailed in the thesis and in the References sections.
This is a well written book; it makes easy and pleasant reading for both experts and physicists working in other areas. The book is almost self-contained. It comprises six chapters. In the first three the author introduces the subject and deals with basic results and analytic tools from quantum optics: quantum theory of light and quasi-probability functions. In the fourth chapter he discusses the quantum-mechanical description of simple optical instruments. The last two chapters are the core of the book; they are devoted to a discussion of quantum tomography, joint measurement of position and momentum and the quantum-optical phase. The author was directly involved in the development of the field, which guarantees a fresh and clear exposition. At the same time he makes an open effort for a general (re)formulation of the subject and to present the `classic' solutions to a number of problems in the area. Overall, the presentation of quantum tomography is shaped by a personal view but it accounts sufficiently for the different approaches discussed in the literature. My only reservation is the way in which connections between classical and quantum tomography are presented. In particular, I find that an explicit statement that classical tomography (inverse Radon transform) cannot be straightforwardly applied to the quantum case should be made. The book was published in 1997. Since then the field has been growing rapidly and impetuously and the book shows its age. Nevertheless, it is still a useful reference tool for active researchers and a nice and valuable introduction for (graduate) students who are entering this area. It is worth noting that only a few books have been published on this subject; Leonhardt's volume is well written and to the point. The book is dedicated to Harry Paul, the supervisor of Leonhardt's postdoctoral thesis and the coauthor of most of his papers in the area. M G A Paris