Description du sujet de thèse

A PhD position is open in the group of Alexia Auffèves (MajuLab ,CQT, Singapore) to work on fundamental aspects of quantum energetics applied to quantum optics. The candidate will explore relations between energy and non-classicality, both to provide new ways to characterize non-classical quantum states of light, and optimize processes to produce them.

Context of the research topic and proposed workplan
Non-classical (a.k.a. non-Gaussian) states of light like photon number states or Schrödinger cat states are precious resources for quantum metrology and quantum computing. They also represent beautiful objects to explore the specificities of the quantum world. Since the early days of quantum optics, an important work is devoted to build criteria of non-classicality, and to relate them quantitatively to technological performances. The presence of negativities in the Wigner function, or the stellar rank, are famous examples of these criteria.
Various strategies are currently used in the lab to produce non-classical states of light, that rely on measurement in the photon number basis, or coupling to optical non-linearities, or both. The PhD project will be devoted to building energetic analyses of these various processes, with the double objective to optimize each process, and to benchmark them as a function of their energy-efficiency.
The beginning of the PhD work will be focused on the quantum states of a single bosonic mode. A key idea is that displacements and squeezing in the phase space cost energy without increasing the metrics of non-classicality. Building on this simple idea, the candidate will propose and optimize processes to produce non-classical states of light under a fixed energy budget. This acquired knowledge will then be used to explore the more complex case of quantum emitters coupled to circuits as in circuit QED or integrated photonics.

Qualifications
- Master degree in quantum physics
- Former internships in theoretical quantum optics and quantum thermodynamics will be considered as a strong plus
- Former internships in quantum optics labs will be considered as a strong plus
- Taste to work in various environments, collaborate with experimentalists, and explore foundational questions.

What We Offer
- The PhD student will enter the newly established MajuLab PhD program: She/he will graduate from Sorbonne Université while realizing their entire PhD in MajuLab, CQT, Singapore.
- Before starting the thesis, the candidate will spend three to five months as an intern in the group (monthly stipend 3,000S$). When entering the PhD program, the candidate will earn a net salary of 5,500 S$/month. A budget is dedicated to participate to conferences, schools and stays in the labs of the experimental partners.
- The student will enjoy working on a pioneering topic of increasing importance for quantum technologies, with a large room for creativity in addressing fundamental questions of quantum physics.

How to Apply
Interested candidates should submit their application and include a detailed CV, a cover letter explaining their interest and fit for the role, two reference letters, and certified grades for the three last academic years.

Contexte de travail

Working environment
Auffèves' group has pioneered the research at the boundary between quantum optics and quantum energetics/thermodynamics, exploiting the richness of quantum optics to explore energetics in the quantum realm, and building new energetic figures of merit to witness quantum effects or assess the cost of quantum resources. The candidate will be closely supervised by senior research fellows, and will have the opportunity to collaborate with excellent experimental groups worldwide in circuit QED, cavity QED, and quantum photonics. The group is part of MajuLab, a joint international lab whose signatory institutions are the French Centre National de la Recherche Scientifique (CNRS), the Universite Côte d'Azur (UCA), Sorbonne Université (SU), the National University of Singapore (NUS) and the Nanyang Technological University (NTU). The group is physically based inside the Centre for Quantum Technologies, which offers a very stimulating environment for quantum foundations and quantum technologies and the potential for many discussions and collaborations.

Contraintes et risques

No risk identified