Quantum Cryptography, Hardware Security, Quantum Internet Protocols, Quantum Cloud Computing, Verification of Quantum Technology, Experimental Implementation of Quantum Protocols, Foundation of Quantum Mechanics, Quantum Parallel Computing, New Models for Quantum Computing, Quantum Simulation and Learning

Quantum error correcting codes, quantum cryptography and quantum networks.

Security, Delegated Computing, Verification

Cryptography, post-quantum cryptography, protocol zoo, hardware security.

Quantum machine learning, benchmarking and verification of quantum computation, secure communications.

Quantum randomness / Quantum Supremacy / Verification of near-term quantum devices

Benchmarking, Quantum Networks, Quantum Protocol Zoo

Cryptography, post-quantum cryptography, protocol zoo, hardware security.

Randomized benchmarking, certification, quantum simulation, analogue quantum simulation, scalable testing, approximate t-designs

Foundation, nonlocality and contextuality

Quantum Cryptography, Post-Quantum Cryptography, Delegated Blind Quantum Computing, Verification of Quantum Computing, Provable Security

Quantum Cryptography, Post-Quantum Cryptography, Delegated Blind Quantum Computing, Verification of Quantum Computing, Provable Security

Quantum Cryptography, Post-Quantum Cryptography, Delegated Blind Quantum Computing, Verification of Quantum Computing, Provable Security

Quantum machine learning, quantum advantage, testing, variational algorithms, device independent cryptography

Quantum Computational Supremacy, Verification, Benchmarking, NISQ Technology, Classical Simulation of Quantum Systems, Quantum Computing Software

Quantum advantage, Cryptography, Protocol Zoo, device independent cryptography

Quantum cryptography, secure multiparty quantum computing.

Quantum machine learning, quantum advantage, privacy-preserving machine learning, generative models, statistical learning theory

Quantum Simulation, Verification and benchmarking

Verification and Benchmarking

- Ieva Cepaite (Master and Project Student)
- Flaviu Cipcigarn (Project student)
- Julien Du Crest (Project student)
- Raphael Dias (Visiting Ph.D. student)
- Leonardo Disilvestro (Master and project student)
- Tom Douce (Postdoc)
- Vedran Dunjko (Postdoc and Ph.D. student)
- Patric Fulop (Project student)
- Alexandru Gheorghiu (Postodc, PhD and Master student)
- Matty Hoban (Postdoc)
- Borislav Ikonomov (Master student)
- Marc Kaplan (Postdoc)
- Theodoros Kapourniotis (Postdoc, Ph.D. and Master student)
- Pia Kullik (Project student)
- Shane Mansfield (Postdoc)
- Martin Marinov (Project student)
- Anna Pappa (Postdoc)
- Einar Pius (Ph.D. and Master studnet)
- Shraddha Singh (Master Student)
- Phivos Sofokleous (Project student)
- Iskren Vankov (Project student)
- Petros Wallden (Postdoc)

## Elham Kashefi

**Keywords**:

Quantum Cryptography, Hardware Security, Quantum Internet Protocols, Quantum Cloud Computing, Verification of Quantum , Experimental Implementation of Quantum Protocols, Foundation of Quantum Mechanics, Quantum Parallel Computing, New Models for Quantum Computing, Quantum Simulation and Learning

## Harold Ollivier

**Keywords**:

Quantum error correcting codes, quantum cryptography and quantum networks.

I currently focus on projects related to the advent of a quantum internet such as: what protocols could be useful to run on such networks, how to improve them to take into account realistic noisy devices, and how to benchmark and asses the quality of networks.

## Ulysse Chabaud

**Keywords**:

Quantum certification / Continuous variable quantum information theory / Quantum optics / Quantum cryptography

How do we check the correct functioning of the quantum device? Answering this question is a timely problem in the absence of fault-tolerant mechanisms, for benchmarking existing and upcoming quantum technologies.

The task of certification may vary depending on the context: fundamental research, industrial quantum device, or even delegated quantum computing and quantum cryptography. In all these cases, what may vary is the level of trust one wants to guarantee, as well as the assumptions one is ready to make.

Our contribution is a variety of protocols and techniques covering all these contexts, and using tools from quantum cryptography to guarantee security for the user.

Articles:

– Building trust for continuous variable quantum states, Ulysse Chabaud, Tom Douce, Frédéric Grosshans, Elham Kashefi, Damian Markham, arXiv preprint arXiv:1905.12700 (2019)

– Quantum certification and benchmarking, Jens Eisert, Dominik Hangleiter, Nathan Walk, Ingo Roth, Damian Markham, Rhea Parekh, Ulysse Chabaud, and Elham Kashefi, arXiv preprint arXiv:1910.06343 (2019, Review paper)

Continuous variable quantum information theory:

A great part of the theory already developed for discrete variable quantum information is still missing for continuous variable quantum information. The latter gives different perspectives on quantum information. In addition, continuous variable quantum information has an exciting experimental status, thanks to quantum optics in particular, which enables the scalable generation of large entangled quantum states and provides high efficiency measurements.

Our work covers a variety of subjects: quantum computational supremacy in continuous variable, certification of continuous variable quantum states, theory of non-Gaussian states.

Articles:

– Continuous-variable sampling from photon-added or photon-subtracted squeezed states, Ulysse Chabaud, Tom Douce, Damian Markham, Peter Van Loock, Elham Kashefi, and Giulia Ferrini, Physical Review A, Vol 96 no 6, 062307 (2017)

– Building trust for continuous variable quantum states, Ulysse Chabaud, Tom Douce, Frédéric Grosshans, Elham Kashefi, and Damian Markham, arXiv preprint arXiv:1905.12700 (2019)

– Stellar Representation of Non-Gaussian Quantum States, Ulysse Chabaud, Damian Markham, and Frédéric Grosshans, Physical Review Letters, Vol 124 no 6, 063605 (2020)

Quantum optics:

Quantum optics provides an exciting experimental platform for existing, near-term, and long-term quantum applications. Quantum states of light allow for many possible encodings, with applications ranging from quantum communication, quantum computing and quantum cryptography.

We develop protocols and applications that can be readily implemented using quantum optics.

Articles:

– Optimal quantum-programmable projective measurement with linear optics, Ulysse Chabaud, Eleni Diamanti, Damian Markham, Elham Kashefi, and Antoine Joux, Physical Review A, Vol 98 no 6, 062318 (2018)

– Quantum information processing with coherent states: optimal and programmable toolkit schemes, Niraj Kumar, Ulysse Chabaud, Elham Kashefi, Damian Markham, and Eleni Diamanti, in preparation (2020)

– Quantum weak coin flipping with a single photon, Mathieu Bozzio, Ulysse Chabaud, Iordanis Kerenidis, Eleni Diamanti, in preparation (2020)

Quantum cryptography:

Properties of quantum information such as entanglement and no-cloning allow for cryptographic applications such as quantum key distribution, blind quantum computing, etc. At the same time, adversarial parties also have access to quantum powers, meaning that the security of existing and upcoming protocols have to be proven against quantum adversaries.

With this concern in mind, our work covers a broad range of cryptographic protocols for various applications.

Articles:

– Building trust for continuous variable quantum states, Ulysse Chabaud, Tom Douce, Frédéric Grosshans, Elham Kashefi, Damian Markham, arXiv preprint arXiv:1905.12700 (2019)

– Quantum weak coin flipping with a single photon, Mathieu Bozzio, Ulysse Chabaud, Iordanis Kerenidis, Eleni Diamanti, in preparation (2020)

– Security of Quantum Position Verification BB84-like protocols, Andrea Olivo, Ulysse Chabaud, André Chailloux, and Frédéric Grosshans, in preparation (2020)

## Theodoros Kapourniotis

**Keywords**:

Security, Delegated Computing, Verification

Related papers:

Gheorghiu, Alexandru, Theodoros Kapourniotis, and Elham Kashefi. “Verification of quantum computation: An overview of existing approaches.” Theory of computing systems 63.4 (2019): 715-808.

Mills, Daniel, Anna Pappa, Theodoros Kapourniotis, and Elham Kashefi. “Information theoretically secure hypothesis test for temporally unstructured quantum computation.” QPL/IQSA (2017).

Kashefi, Elham, and Anna Pappa. “Multiparty delegated quantum computing.” Cryptography 1.2 (2017): 12.

Kapourniotis, Theodoros, Vedran Dunjko, and Elham Kashefi. ”On optimising quantum communication in verifiable quantum computing”, Proceedings of the 15th Asian Quantum Information Science Conference (2015)

Dunjko, Vedran, Theodoros Kapourniotis, and Elham Kashefi. “Quantum-enhanced secure delegated classical computing.” Quantum Information & Computation 16.1-2 (2016): 61-86.

Kapourniotis, Theodoros, Elham Kashefi, and Animesh Datta. “Blindness and verification of quantum computation with one pure qubit.” 9th Conference on the Theory of Quantum Computation, Communication and Cryptography (TQC 2014). Schloss Dagstuhl-Leibniz-Zentrum fuer Informatik, 2014.

## Mahshid Delavar

**Keywords**:

Cryptography, post-quantum cryptography, protocol zoo, hardware security.

Like other areas of the security field, quantum technology might have advantages or disadvantages in the field of hardware security. There are several proposals on the design of universal composable cryptographic protocols based on hardware assumptions in classical settings. The question that we are addressing is whether quantum technology threatens the security of hardware assumptions introduced so far or boosts their security by using the features of quantum mechanics. Currently, we are working on Physical Unclonable Functions (PUFs), One-Time Memory (OTM) and Hardware Enclave as cryptographic hardware primitives. The results of our work are found in the following links:

Quantum Physical Unclonable Functions: Possibilities and Impossibilities: https://arxiv.org/pdf/1910.02126.pdf

In this work, we formally define the notion of quantum PUFs (qPUFs) and their security considering different attack scenarios and computational capacity of the attackers. We show the vulnerability of qPUFs against an unbounded quantum adversary as well as quantum polynomial-time (QPT) adversaries where the target of the attack is generating a valid quantum challenge-response pair of the qPUF. On the other hand, we prove qPUFs are secure against QPT adversaries who aim to estimate the correct response to an unknown quantum challenge chosen by another party. Our security proof shows qPUFs provide the required security notion to be used in cryptographic protocols even in the quantum world.

Cryptography and Post-quantum cryptography:

Shor’s algorithm showed the vulnerability of widely-deployed cryptographic algorithms and protocols to the emergence of quantum technology. This initiated wide research on exploring other quantum adversarial algorithms and attack scenarios as well as finding countermeasures to improve the security of cryptographic primitives, algorithms and protocols against quantum adversaries. Our research includes developing quantum adversarial algorithms, proposing quantum secure constructions for known cryptographic primitives and design of quantum-secure cryptographic protocols.

## Mina Doosti

**Keywords**:

Cryptography, post-quantum cryptography, protocol zoo, hardware security.

Like other areas of the security field, quantum technology might have advantages or disadvantages in the field of hardware security. There are several proposals on the design of universal composable cryptographic protocols based on hardware assumptions in classical settings. The question that we are addressing is whether quantum technology threatens the security of hardware assumptions introduced so far or boosts their security by using the features of quantum mechanics. Currently, we are working on Physical Unclonable Functions (PUFs), One-Time Memory (OTM) and Hardware Enclave as cryptographic hardware primitives. The results of our work are found in the following links:

Quantum Physical Unclonable Functions: Possibilities and Impossibilities: https://arxiv.org/pdf/1910.02126.pdf

In this work, we formally define the notion of quantum PUFs (qPUFs) and their security considering different attack scenarios and computational capacity of the attackers. We show the vulnerability of qPUFs against an unbounded quantum adversary as well as quantum polynomial-time (QPT) adversaries where the target of the attack is generating a valid quantum challenge-response pair of the qPUF. On the other hand, we prove qPUFs are secure against QPT adversaries who aim to estimate the correct response to an unknown quantum challenge chosen by another party. Our security proof shows qPUFs provide the required security notion to be used in cryptographic protocols even in the quantum world.

Cryptography and Post-quantum cryptography:

Shor’s algorithm showed the vulnerability of widely-deployed cryptographic algorithms and protocols to the emergence of quantum technology. This initiated wide research on exploring other quantum adversarial algorithms and attack scenarios as well as finding countermeasures to improve the security of cryptographic primitives, algorithms and protocols against quantum adversaries. Our research includes developing quantum adversarial algorithms, proposing quantum secure constructions for known cryptographic primitives and design of quantum-secure cryptographic protocols.

## Ellen Derbyshire

**Keywords**:

Randomized benchmarking, certification, quantum simulation, analogue quantum simulation, scalable testing, approximate t-designs

Publications:

Randomized Benchmarking in the Analogue Setting – E. Derbyshire, J. Y. Malo, A. Daley, E. Kashefi, P. Wallden, arXiv: 1909.01295, currently under review for Quantum Science and Technology, IOP Journal.

## Pierre-Emmanuel Emeriau

**Keywords**:

Foundation, nonlocality and contextuality

## Yao Ma

**Keywords**:

Cryptography, Hardware Security, Delegated Computing

## Dominik Leichtle

**Keywords**:

Quantum Cryptography, Post-Quantum Cryptography, Delegated Blind Quantum Computing, Verification of Quantum Computing, Provable Security

## Alexandru Cojocaru

**Keywords**:

Quantum Cryptography, Post-Quantum Cryptography, Delegated Blind Quantum Computing, Verification of Quantum Computing, Provable Security

## Léo Colisson

**Keywords**:

Quantum Cryptography, Post-Quantum Cryptography, Delegated Blind Quantum Computing, Verification of Quantum Computing, Provable Security

## Daniel Mills

**Keywords**:

Quantum Computational Supremacy, Verification, Benchmarking, NISQ Technology, Classical Simulation of Quantum Systems, Quantum Computing Software

## Sima Bahrani

**Keywords**:

Benchmarking, Quantum Networks, Quantum Protocol Zoo

## Brian Coyle

**Keywords**:

Quantum machine learning, quantum advantage, testing, variational algorithms, device independent cryptography

I have also investigated hybrid quantum-classical models known as variational quantum circuits (similar to a classical neural network) as applications in machine learning and more generally in quantum algorithm discovery. These are suitable for near term quantum devices as they require a minimal quantum overhead, with the heavy lifting done by a classical processor to help the quantum model learn so solve a particular problem. They are also somewhat tolerant to destructive quantum noise which can kill any advantage in practice. In particular, we have studied them as generative models in a form called a ‘Born machine’ and as quantum classification models. Mostly, these are implemented using the Rigetti Forest quantum platform, and have been run on real quantum hardware.

Papers:

Robust Data Encodings for Quantum Classifiers: ArXiv to appear.

The Born Supremacy: Quantum Advantage and Training of an Ising Born Machine https://arxiv.org/abs/1904.02214.

Certified Randomness From Steering Using Sequential Measurements: https://www.mdpi.com/2410-387X/3/4/27.

One-Sided Device-Independent Certification of Unbounded Random Numbers: https://arxiv.org/abs/1806.10565v2.

## Rawad Mezher

**Keywords**:

Quantum randomness / Quantum Supremacy / Verification of near-term quantum devices

Recently, my research has shifted towards verification of near term quantum devices either currently doable experimentally, or expected to be implemented in the near-term.

## Paul Hermouet

**Keywords**:

Quantum advantage, Cryptography, Protocol Zoo, device independent cryptography

I work on making a survey as exhaustive as possible on these possibilities/impossibilities results and what advantages have quantum protocols over the classical ones.

## Armando Angrisani

**Keywords**:

Quantum machine learning, quantum advantage, privacy-preserving machine learning, generative models, statistical learning theory

## Niraj Kumar

**Keywords**:

Quantum machine learning, benchmarking and verification of quantum computation, secure communications.

## Luka Music

**Keywords**:

Quantum cryptography, secure multiparty quantum computing.

## Former Members

Nathansh Mathur

Rhea Parekh

Castagnet Cyril