Research

Ultrafast spectroscopy of advanced CQDs

At the Los Alamos National Laboratory, I work in the team of Victor Klimov on the spectroscopy of advanced CQDs. Those include magnetically-doped CQDs with applications to photoemission and photochemistry (see our Nature Photonics paper), "Auger-suppressed" CdSe-based core-shell structures for visible LEDs and lasers, as well as new infrared-absorbing CQDs for solar energy.

My work is dedicated to the spectroscopy of CQD samples from their bare form in liquid solution to CQD solids and to CQD devices, allowing to understand their fundamental properties and how they translate to real-life applications.

Pics:

(TOP) Optically-injected ASE in a fuly working, high current CQD LED (https://arxiv.org/abs/2204.01929)

(BOTTOM) Multicolor continuously-graded CQDs (cg-QDs) excited by a green laser - (https://int.lanl.gov/news/news_stories/2021/august/0805-quantum-dots.shtml)

Infrared detection with CQDs

Infrared imaging allows to visualize electromagnetic radiation beyond the visible range, in the long-wavelength domain. It is relevant for a broad range of applications, from defense to automation, food processing and chemical sensing. Current high performance solutions for SWIR, MWIR and LWIR imaging rely either on complex and expensive epitaxial structures (InGaAs on InP, HgCdTe on CZT...) or on thermal detectors (bolometers) suffering from very low temporal bandwidth. Colloidal semiconductor nanocrystals with tunable absorption in the infrared range allow the design of a new generation of cheap, solution-processable infrared detectors.

Pics:

(TOP) Two generations of cryostats built during my PhD to investigate the performance of single pixel MWIR detectors based on HgTe and HgSe nanocrystals.

(MIDDLE) Absorption spectra of interband HgTe (red), intraband HgSe (blue) and intraband HgTe (green) ranging from SWIR to FIR.

(BOTTOM) Imaging with infrared CQD. Left: SWIR image obtained with a HgTe/CMOS hybrid detector (see https://pubs.acs.org/doi/abs/10.1021/acs.chemrev.0c01120). Right: MWIR image of the tip of a soldering iron with a scanning HgSe/HgTe single-pixel device (see https://www.nature.com/articles/s41467-019-10170-8)

Other topics

Transport in 2D materials and 2D/CQD hybrids

Time-resolved UPS/XPS at Soleil synchrotron: rationalizing device design

High pressure, low temperature infrared spectroscopy: exploring Hg-based CQDs phase diagram

Optoelectronics and carrier transport in perovskite quantum dots

CQD-based light sources

Ultrafast optics