Missions

Nanophononics is a promising field with great potential for controlling sound and heat at the nanometer scale. Over the past thirty years, intensive research on the vibrational properties of semiconductor multilayer systems has led to a deep understanding of acoustic phonons in such structures. However, the development of phononic devices operating in the GHz–THz range remains an open area, offering opportunities for new ideas and applications.

Nanophononics plays a key role in engineering thermal transport in nanoscale electronic devices and could open a new pathway for quantum communications, using phonons as carriers of information.

We will investigate the dynamics of phonons in acoustic resonators formed by Bragg mirrors and thin films of responsive materials (VO₂, mesoporous SiO₂), capable of confining interface modes. Through high-resolution Brillouin scattering and coherent acoustic phonon generation experiments, we will study the dynamical behavior of microstructured systems.

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

Activités

Numerical simulation and optimization of acoustic and optical resonators

Design and fabrication of nano-acoustic devices

Development of the experimental setup for the optical characterization of coupled micropillars and opto-phononic resonators

Execution of high-resolution Raman and Brillouin spectroscopy experiments, as well as coherent acoustic phonon generation measurements

Compétences

The candidate should have a strong background in solid-state physics, nanostructures, and opto-acoustic interactions, as well as proven experience with ultrafast experimental techniques dedicated to the study of phonons.

The desired skills include:

Extensive experience (≥ 4 years) in the implementation and operation of pump–probe techniques for the coherent generation and time-resolved detection of acoustic phonons (20–300 GHz range). A solid command of optical alignment, femtosecond pulse timing control, and transient signal analysis is highly desirable.

Numerical simulation and optimization of acoustic and optical resonators (using COMSOL Multiphysics or equivalent tools) for the design and fine-tuning of structures enabling the simultaneous confinement of phonons and photons.

Design, micro/nanofabrication, and characterization of nano-acoustic and opto-phononic devices, including Bragg resonators and thin films of responsive materials (VO₂, mesoporous SiO₂, etc.).

Proficiency in high-resolution spectroscopic techniques (Raman, Brillouin) for investigating vibrational properties and phonon dynamics in micro- and nanostructured systems.

Solid knowledge of light–matter interactions, thermal transport at the nanoscale, and photon and phonon confinement phenomena.

Additional skills in advanced experimental data processing, scientific programming (Python, MATLAB), and a high level of experimental autonomy will be particularly valued.

Contexte de travail

The postdoctoral position will be carried out within the Quantum Optics in Semiconductor Nanostructures Group (GOSS) at the Centre for Nanoscience and Nanotechnology (C2N), a joint research unit of CNRS and Université Paris-Saclay.

C2N brings together more than 120 researchers and 80 engineers, technicians, and administrative staff. It hosts a state-of-the-art technology platform featuring cleanroom facilities exceeding 2,900 square meters. The GOSS group consists of eight researchers and includes more than 25 PhD students and postdoctoral fellows.

The position falls under a sector subject to protection of scientific and technical potential (PPST) regulations, and therefore, in accordance with French law, your appointment must be authorized by the competent authority of the Ministry of Higher Education and Research (MESR) prior to your arrival.

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 position involves the use of laser systems.