LifeTEM – Time-Resolved Cathodoluminescence in an Ultrafast TEM applied to InGaN/GaN Quantum Wells

Research project selected under the 2022 call for proposals

Principal Investigator : Sophie Meuret – sophie.meuret@cemes.fr

Involved Teams :

CEMES / In situ interferometry and instrumentation for electron microscopy, I3EM
LPCNO / Optoéltectronique Quantique, OPTO
CEMES / Nano-Optics and Nanomaterials for Optics, NeO

Type of project : Collaborative Project

Date (start/end) : 2021 – 2025

Sketch of the Cathodoluminescence set-up in the FemtoTEM microscope. A parabolic mirror collects the light emitted by the material after excitation by a pulsed electron beam. The light is send either to a spectrometer or a photon counting scheme.

Cathodoluminescence spectroscopy (CL) performed in a transmission electron microscope (TEM), is one of the best techniques to link the optical properties of atomically design structure with their atomic feature. However, until recently, CL spectroscopy in TEM could not observe the full optical dynamics. The CEMES demonstrated time-resolved CL in an ultrafast TEM for the first time in 2021. The lifeTEM project will use this one-of-a-kind experiment to investigate the carrier dynamics in the technologically-relevant InGaN/GaN heterostructures with unprecedented spatio-temporal resolution. Taking advantage of the CEMES team’s unique technological advances as well as the LPCNO team’s state-of-the-art optical spectroscopy expertise, through 3 studies we will both improve our understanding of InGaN/GaN optical properties at the nanoscale and expand the possibilities and limits of our unique TRCL experiment.