Reference : UMR8502-LUIGAL-007
Workplace : ORSAY
Date of publication : Monday, September 12, 2022
Type of Contract : FTC Scientist
Contract Period : 24 months
Expected date of employment : 2 January 2023
Proportion of work : Full time
Remuneration : 2889,51 et 3321,55 euro per month
Desired level of education : 5-year university degree
Experience required : Indifferent
The coupling of relativistic electrons to matter and optical fields has opened a vast field of investigation. Indeed thanks to cutting edge electron microscopes and the development of remarkable spectroscopy concepts and tools (electron energy loss and gain spectroscopy, cathodoluminescence …), nanooptical investigations with resolutions down to the atomic and µeV resolutions are now possible. Besides remarkable achievements in the visible-UV range, including the routine nanometer scale measurement of plasmons or quantum emitters, and more recently high finesse cavities, the mid-to far IR regime has got new traction. Indeed, novel technologies allow single atom vibrational spectroscopy [Hage et al., Science 2020], strong plasmon-phonon coupling investigation at the nanoscale [Tizei et al., Nano Letters, 20, 2973 (2020)] or three-dimensional and vector mapping of phonon modes on nanoparticles surfaces [Li et al., Science 371 1364 (2021)]. Nevertheless, exploring molecular vibrational modes of individual molecules with high spatial resolution has never been done. However, we believe that this a possibility sitting around the corner thanks to the possibility of performing EEGS in a ultra-high energy resolution electron microscope.
In this 2 year post-doc project, the successful candidate will explore electron spectroscopies of molecules confined in space using a combination of EELS and EEGS in the mid to far IR. Specialized samples will be created in house, using technique already developed at our laboratory. The project will first focus on large molecular volumes, but will aim at the individual level from the start. The stability of molecules in the tens of seconds range under electron irradiation [Tizei et al., Phys. Rev. Lett., 113 185502 (2014)] shows that single molecule vibrational-spectroscopy should be feasible. Also, the development of new detection schemes using event driven detectors will undoubtedly benefit beam-sensitive materials, such as molecules [Y. Auad, et al., arXiv:2110.01706 (2021)].
*Sample preparation for electron spectroscopy experiments;
*Realization of electron spectroscopy experiments in a state-of-the-art electron microscope;
*Participation in conferences;
We are seeking candidates with a curious mind, a taste for experimental work, and a will to tackle a totally new field of nanospectrosopy in the competitive domain of electron-based spectroscopies. Electron microscopy and spectroscopy skills are required, and a knowledge of optical techniques will be a plus.
The candidate will have access to the STEM group (LPS Orsay) extensive experience on electron spectroscopy instrumentation and to state-of-the-art electron microscopes, specifically one (ChromaTEM) optimized for high energy resolutions spectroscopies (EELS, EEGS, CL) at high spatial resolution and cryogenic temperatures. The use of state-of-the-art event-based detectors for spectroscopies will be an undoubtful benefit for this project.
Constraints and risks
There are no associated risks;
We talk about it on Twitter!