| General Information | The Mid Infrared (MIR) spectrum covers a wide range of frequencies (20-60 THz – 15-5μm),
which calls for a wide variety of technologies in the fields of optics and optoelectronics. In this
context, our team has been developing for several years ultrafast MIR detectors based on IIIV
semiconductor heterostructures [1]. Nowadays these detectors have reached 3dB
radiofrequency (RF) bandwidths of ~100 GHz, an unsurpassed performance to date. They
consist of arrays of quantum-well photo-detectors coupled to plasmonic antennas [2], and their
characteristics are well-suited for many applications such as gas/sensing/spectroscopy,
coherent imaging, free-space communications, astrophysics or the generation of THz waves
by photomixing of MIR lasers [3-6].
The objective of this PhD project is to demonstrate a new generation of photo-detectors with increased performance, thanks to the design of new types of antennas, and of new heterostructures with a stronger photoconductive gain by optimizing their quantum design. In particular, in the 8-12μm range, we aim for (i) an increase in responsivity by a factor of 2-3 compared to the state of the art; (ii) an extension of the 3dB RF bandwidth up to 200 GHz; (iii) the design of novel antenna architectures compatible with CMOS readout. |
| Context: | The successful candidate shall be enrolled on a PhD program of the Lille University doctoral school. The PhD will take place within the project COMPTERA, funded by the PEPR (Programme et Équipement Prioritaire de Recherche) Electronics, in collaboration with Ecole Normale in Paris and CEA-LETI in Grenoble. The work will be carried out within the THz- Photonics group of IEMN laboratory. The group has a long-lasting experience in the conception, design and demonstration of novel optoelectronic devices ranging from the THz to the MIR (THz- Photonics-Group publications), and is fully equipped for the MBE growth, fabrication and characterization of the devices realized in this project. |
| Constraints and risks | The candidate is expected to travel for short periods in France and abroad |
| Supplementary information | The work of this PhD project can be schematically divided in 2 parts:
Electromagnetic and quantum design of the antennas and of the photo-detectors active region respectively, with the help of available finite element codes. Main goal: obtain a reliable model for the prediction of the electronic transport and for the optimization of the responsivity as a function of temperature and doping density. Fabrication in clean-room environment (e-beam lithography, e-beam evaporation, plasma enhanced chemical vapor deposition, ICP etching etc) Electrical and optical characterization of the photodetectors, through |
| Required skills | Motivated PhD fellow, capable of bringing new ideas.
Good attitude towards team-work. Solid knowledge of electromagnetics, quantum mechanics and optoelectronic devices Experience with finite element electromagnetic simulation codes is a plus Experience in programming for instrumentation control (Labview, Phyton) desired. Good level of English, spoken and written. Good writing skills (writing of papers and reports) are highly desired |
Host Unit:
IEMN UMR CNRS 8520
Avenue Poincaré
59652 VILLENEUVE D ASCQ CEDEX
www.iemn.fr
Start date:
September-December 2023.
Applications should be sent to:
Stefano Barbieri
stefano.barbieri@iemn.fr
Stefano Barbieri – web page
English (UK) 
Français