PhD position, Experimental Ultrafast Optics, CELIA, Talence, France (Deadline: 31.05.2025)
Postcompression of high-energy picosecond pulses with a flat-top spatial distribution
Position Description
Over the past decade, Ytterbium laser technology has sparked a true revolution in laser-based sciences. With the ability to provide high-repetition-rate, high-power laser sources, it has opened new fields of investigation. At the same time, research programs as HORIZON at CELIA have emerged worldwide to push the Ytterbium technology to the kW level with an energy of 1 Joule at 1 kHz repetition rate with picosecond pulse durations. However, long limited to the picosecond regime, the combination of Ytterbium lasers with femtosecond postcompression systems based on nonlinear optics in gases or transparent media has made it possible to increase the peak power of these systems to the terawatt (TW) level, challenging the long-dominant Ti:sapphire technology.
The objective of this doctoral work is to conduct a theoretical and experimental study on the post-compression of high-energy picosecond pulses with a “flat-top” spatial distribution. Unlike post-compressed pulses obtained from Gaussian beams, this shaping will ensure a uniform pulse duration across the entire aperture, thereby minimizing the temporal impact of spatio-temporal coupling at the focal point of interaction. During this thesis, a postcompression beamline based on self-phase modulation in thin films or silica plates with flattop beam profiles will be explored using the HORIZON facility, which delivers picosecond pulses at 1 kHz with energies ranging from 20 mJ to over 500 mJ. Additionally, the PhD student will study the effects of “top-hat” shaping on the final spatio-temporal coupling of post-compressed pulses at the target. All the equipment for the postcompression beamline has been already procured. Simulations of the post-compression process and the time-space propagation up to the interaction point will also be conducted. This doctoral work aims to bring HORIZON to a unique world-class TW laser facility with kW average power.
Requirements
Master degree in physics or photonics preferably including qualifications in the areas of optics, lasers physics and nonlinear optics.
Experience in ultrafast optics will be an asset
Strong skills and motivation for experimental work
Knowledge in numerical methods and programming (Matlab, Python)
Good communication skills in English are required, basic notion of French would be desirable.
Working at CELIA, Université de Bordeaux
CELIA (CEntre Lasers Intenses et Applications) is a research unit located just 15 minutes by tram from downtown Bordeaux. Under the auspices of Université de Bordeaux, CNRS and CEA, his main missions are to develop research related to intense lasers from attoscience to laser fusion and applications. 5 research groups with expertise at the intersection of fundamental physics and high-tech applications offer to PhD students at CELIA a rich scientific environment. The proposed research work will be carried out in the GOLF group, whose research focus is on the physics and technologies of intense femtosecond lasers with high average power and high energy, fiber or solid-state lasers, and nonlinear optics.
More information at celia-bordeaux.cnrs.fr
This doctoral work is funded by LIGHT Sciences & Technologies Graduate Program (LIGHTS&T), an integrated interdisciplinary master’s and doctoral program in photonics and quantum technologies. LIGHTS&T offers to funded PhD student a rich and mutidiscplinary environment with specialized training programs or events organized for PhD students. LIGHTS&T supports also international mobility through mobility grants and promotion of outstanding research results obtained during the thesis. Listed as a UNESCO World Heritage site for its architecture and historic center, with iconic landmarks such as the Garonne River waterfronts and the “Miroir d’eau,” Bordeaux offers a unique opportunity to live in a setting rich in history and an aesthetic that inspires daily life.
The city’s proximity to the Atlantic Ocean, Arcachon Bay, and Bordeaux vineyards also provides an exceptional living environment.
More information – Contact
stephane.petit@u-bordeaux.fr, Université Bordeaux, CELIA, 33400 Talence, France
Candidature Application procedure
1. For more informations contact first the PhD supervisor : stephane.petit@u-bordeaux.fr,
2. LIGHTS&T organizes a recruitment competition for candidates on the thesis topic. The selection will be based on the criteria of excellence and the fit of the student’s profile with the topic. The application to be completed by the candidate must include the following documents:
The title and summary of the thesis topics.
Detailed curriculum vitae with academic results and a list of publication if applicable.
Cover letter
University grade transcripts (or engineering track) for Master Sc (1 and 2) showing the candidate’s rankings.
A certificate of successful completion of the Master’s degree or equivalent, if applicable.
One or two Letters of recommendation (from the Master’s internship supervisor, Master’s program coordinator, etc.).
An electronic copy of the Master’s thesis (if available).
Applications must be sent to contact.light-st@u-bordeaux.fr with the PhD supervisor
(stephane.petit@u-bordeaux.fr) in copy.
