Reference : UMR7010-JEAETE-001
Workplace : NICE
Date of publication : Wednesday, May 11, 2022
Scientific Responsible name : Sébastien Tanzilli
Type of Contract : PhD Student contract / Thesis offer
Contract Period : 36 months
Start date of the thesis : 5 September 2022
Proportion of work : Full time
Remuneration : 2 135,00 € gross monthly
Description of the thesis topic
Rare-earth ion-doped crystals constitute a unique platform to implement a wide variety of protocols for storage and manipulation of quantum information. This is notably due to their record coherence properties and the scalability they offer. Storage time of the order of one hour could be demonstrated with 'non-Kramers' ions, with a protocol opening the way to frequency multiplexed storage: the atomic frequency comb . State-of-the-art storages were realized with 'bulk' materials which set a limit in terms of scalability and storage performances. Several paths were already explored for realizing waveguides in these crystals, by using integration techniques that are mature for other applications. However, the performances memories in these waveguides as well as the perspectives they open in terms of integration of multiple functionalities on a given substrate remain to date limited .
The objective of this thesis is to develop a novel architecture for realizing integrated quantum memories. It will consist in a ridge waveguide on a silica substrate, allowing a guiding of light with a step index. The strength of this architecture is that it will permit a high efficiency addressing of the rare earth ions (in order to increase the storage efficiency to record levels), and will allow to realize coupling with waveguides inscribed on the substrate, to couple several memories on the same substrate.
The memories will be realized on praseodymium-doped yttrium orthosilicate (Pr:Y2SiO2), a rare-earth of strong interest, thanks to its atomic structure and its strong light coupling for a 'non-Kramers' ion .
The storage of small amplitude photonic states will eventually be realized thanks to the atomic frequency comb protocol, showing the validity of the chosen approach.
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 M. Sabooni et al., Phys. Rev. Lett. 110, 133604 (2013).
The PhD will be done at the Institut de Physique de Nice, first at campus Valrose (2022) then on the new facilities in plaine du Var (moving planned on winter 2022-2023).
The applicant will work in the team 'Quantum Information and Photonics', a worldwide renowned team in quantum photonics (quantum communication, integrated photonics, continuous-variable photonic states manipulation, quantum metrology), composed of 9 permanent researchers and ~10 PhDs and Post-docs.
This project will be done within an ANR funded project 'WAQUAM', whose description can be found at the following address: https://anr.fr/Projet-ANR-21-CE47-0001.
It will also be part of a 'Plan quantique' national project 'Qmemo' involving researchers from Sorbonne Université (Paris), Néel Institute (Grenobles) and Chimie Paris (Paris).
Collaborations with European groups are also envisaged (University of Geneva, TU Delft, ICFO Barcelona, Heriot-Watt Edinburgh, University of Milano).
Constraints and risks
The position will imply to perform experimental tasks in optical setups with class IV lasers, therefore specific protection equipment (goggles, protection cardboards, etc.) will be worn and installed.
The candidate should have a background on quantum light-matter interaction. Skills in experimental optics would also be an asset for the applicant, given the numerous fine alignment the experiment will require.
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