Team : QI
Quantum Information and Quantum Networks
In quantum information we use quantum systems to process information promising great benefits in security and efficiency. The two seminal results which started the field span computation and cryptography. Using Shor’s algorithm quantum computers can factor large numbers into primes with exponential gain in efficiency over the best classical algorithms. Quantum key distribution facilitates communication between two parties with security impossible classically.While quantum computers are still out of reach technologically, quantum key distribution is well developed and indeed already commercialised.
In the meantime, there are an increasing number quantum information applications and technological developments beyond QKD, but well below a full scale quantum computer. In computation we have seen the development of specialised computational models which are technologically much more feasible, for example boson sampling and instantaneous quantum computation, but which are still believed to demonstrate complexity advantages over classical computers. In communication and cryptography, we have seen the development of more protocols such as coin flipping and bit commitment where quantum advantages are apparent. At the same time interim sizes of up to 10 controlled qubits are becoming experimentally more and more accessible and compact as they even become placed on chips.We are getting better and better quality quantum channels, reaching longer distances (around 100 km in optical fibre). IBM have very recently put online a universal quanutm computer over 5 qubits - though well below the size where any complexity benefit can be seen, it is an exciting development towards a networked future of such quantum devices (as well as an excellent opportunity for education and training).
One branch of my work since my PhD has been centred on the question of what can be done with this exciting situation, in particular in the setting of quantum networks. We have developed a vision of a hybrid quantum-classical network, where many devices of differing powers, interact for new functionalities.
At the same time I have been studying the interplay between these quantum applications and physics. On the one hand understanding the role of quantum phenomena such as entanglement , non-locality and contextuality, helping us to search for optimal ways of implementing and developing quantum applications. On the other hand understanding what quantum information has to say about fundamental questions in physics.
: 07/05/2017 - 15h30 - Site Jussieu-Amphi DurandJury members
Frédéric Magniez, [Rapporteur]
Prakash Panangaden, [Rapporteur]
Stephanie Wehner, [Rapporteur]
4 PhD students (Supervision / Co-supervision)
- MEZHER Rawad : Aléatoire pour le traitement de l'information quantique .