Missions

The goal of the project is to explore the amplification of surface acoustic waves coupled to a high mobility electron gas through the acoustoelectric effect, in view of developing non-linear integrated photonic-phononic circuits. We will use a well known material system combining piezoelectricity and relatively high mobility electron gas: AlGaN/GaN. This will enable several functionalities, the first one being the ability to modulate the 2DEG electronic density using a gate. Using the transparency of GaN at near-IR and MIR wavelength we will then develop hybrid photonic-phononic integrated circuits leveraging acoustoelectric amplification to enhance the acousto-optic interaction on the micrometer scale.

Activités

The recruited person will join the project from the initial stage. Initial steps are the fabrication and characterization of passive delay lines on GaN/Sapphire, and the introduction of the 2DEG to gauge the magnitude of the acoustoelectric effect, completed by numerical simulations. The acoustoelectric active structure will then be integrated in photonic circuits at near-IR and mid-IR wavelengths. Depending on the results, development of hybrid integration of III-V on LNOI will also be considered.

Compétences

Candidates must have a PhD in Physics with a strong cleanroom fabrication experience (preferably but not necessarily on III-V semiconductors). The project is experimental in essence, applicants are expected to have an expertise in electrical device characterization, as well as some knowledge to build and develop optical setups. Experience in numerical simulations (COMSOL in particular) as well as some coding skills will be appreciated. Prior knowledge on surface acoustic wave physics will be considered a strong asset, but is not mandatory.

Contexte de travail

The position is hosted in the Centre for Nanosciences and Nanotechnologies (C2N), a joint CNRS – Université Paris Saclay laboratory in Palaiseau, with a state-of-the art cleanroom, a renowned expertise in nanofabrication, and a thriving multidisciplinary research environment spanning various areas of quantum physics, nanophysics and photonics.
This project extends the current activities of the ODIN/MIR-THz group on acoustic wave devices in the frame of the Acousto-MIR ANR Project. The aim of this ANR project is to propose GaAs/AlGaAs acousto-optic devices for integrated infrared photonics in the 8-10 µm range. Notably, we already built a scanning heterodyne vibrometer allowing interferometric mapping of surface acoustic waves with sub-µm lateral resolution. This working experiment will greatly simplify the characterization of acoustoelectric devices, allowing contactless measurement of acoustic waves. The epitaxy of GaN/AlGaN heterostructures is performed by collaborators at CHREA, and the project will benefit from collaborations with the MiNaPhot team for integrated photonics perspectives.

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.