Description du sujet de thèse

Nanophononics is a promising field with the potential to manipulate sound and heat at the nanometer scale. Over the past thirty years, research on the vibrational properties of systems composed of semiconductor layers has been intense and has led to a deep understanding of acoustic phonons in these structures. However, the development of phononic devices operating in the GHz to THz range remains an open area for new ideas and applications.

Nanophononics is essential for engineering thermal transport in nanometric electronic devices and could reveal a new path in quantum communications using phonons as information carriers. We will study the dynamics of phonons in acoustic resonators formed by semiconductor Bragg mirrors capable of confining an interface mode. Using high-resolution Brillouin scattering experiments and experiments on coherent generation of acoustic phonons, we will investigate the dynamics of microstructured systems.

We propose to study systems in which light (near-infrared) and acoustic phonons (20 to 300 GHz) can be confined simultaneously.

Activities:
Numerical simulation and optimization of acoustic and optical resonators
Design and fabrication of nano-acoustic devices
Development of experimental setups for optical characterization of coupled micropillars and opto-phononic resonators
Performing high-resolution Raman and Brillouin spectroscopy experiments, and experiments on coherent generation of acoustic phonons

Expected skills:
Strong background in general optics
Knowledge in nanophotonics and design of photonic or phononic crystals
Motivation for numerical simulation of opto-phononic structures
Ability to work in a team and interact with team members
Experience in setting up micro-photoluminescence and/or spectroscopy experiments

Contexte de travail

The PhD will be carried out within the Quantum Optics in Semiconductor Nanostructures Group (GOSS) at the Center for Nanoscience and Nanotechnology (C2N), a joint unit of CNRS and Université Paris-Saclay.
C2N brings together more than 120 researchers and 80 engineers, technicians, and administrative staff. It is equipped with a state-of-the-art technology platform, including cleanrooms covering over 2,900 square meters.

The GOSS group consists of 8 researchers and includes more than 25 PhD students and postdoctoral researchers.

The position falls under the Protection of Scientific and Technical Potential (PPST) framework, and therefore, in accordance with regulations, your appointment must be authorized by the competent authority of the French Ministry of Higher Education and Research (MESR).

Le poste se situe dans un secteur relevant de la protection du potentiel scientifique et technique (PPST), et nécessite donc, conformément à la réglementation, que votre arrivée soit autorisée par l'autorité compétente du MESR.

Contraintes et risques

The activities imply the use of lasers.