Graphene - Quantum Dot Photodetectors
Combining high mobility graphene transistors with efficient light absorbing colloidal quantum dots may pave a way for cheap, high resolving infrared photodetectors. Light is absorbed in the Quantum Dot layer, creating excitons. One charge carrier type is transferred faster to the biased graphene transistor, leading to an additional electric field. This is measured by a current change in the graphene transistor. We are investigating the detailed mechanism of these graphene-QDs photodetectors, expanding the range of spectral photoresponse, increasing the detectivity, and scalling down to the device size below the light wavelength.
Further sources:
Master projects
Our lab offers a variety of Master projects for students.
For more details do not hesitate to contact responsible persons.
| Title | Contact person(-s) |
|---|---|
| THz Boradband Metalenses | Elana Mavrona |
| Time Resolved Photoluminescence Spectroscopy and Simulations | Mirjana Dimitrievska |
| Charge and heat transport through graphene nanoribbon based devices | Mickael Perrin |
| Decoding Alzheimer’s Protein Aggregation in Body Fluids | Peter Nirmalraj |
| Machine Learning Augmented Red Blood Cell Imaging and Analytics | Peter Nirmalraj |
THz Broadband Metalenses
The goal of this Master project is the simulation and fabrication of Terahertz (THz) broadband metalenses>
Metalenses offer significant advantages over classical lenses by allowing compactness and enhancing functionality of optical systems. In this project, the student will design, numerically simulate, and fabricate metalenses operating in the 0.1–1 THz frequency range. Simulations will be performed using Comsol Multiphysics, while fabrication methods will include 3D printing and molding. The work will be conducted at Lepto GmbH, a spin-off company of Empa in Dübendorf.
THz radiationlies between the microwave and infrared regions of the electromagnetic spectrum. THz radiation has unique properties such as non-ionizing interaction with matter, penetration of many non-conductive materials, and sensitivity to molecular vibrations. This makes it ideal for imaging, spectroscopy, and sensing. Importantly, THz frequencies are emerging as a key enabler for next-generation high-speed telecommunications (6G), offering ultra-broadband data transfer and novel satellite communication possibilities.
Type of work: 50% theory, 50% laboratory
Position: 1 Master student
Contact: Interested candidates should contact Dr. Elena Mavrona at eleni.mavrona@empa.ch or elena@lepto.ch.