Optoelectronics in transition metal dichalogenides

Two-dimensional transition metal dichalcogenides are few-atom thick materials. Some of them are semiconductors with a direct bandgap. They thus offer exciting perspectives for a new generation of optoelectronics devices, operating with an extremely low amount of active material, compared to existing technologies. From the physical point-of-view, these semiconductor materials are also quite different from those used in conventional optoelectronics. Their low dimensionality is responsible of a very peculiar electronic band structure and very strong Coulomb interactions. As a result, the behavior of an electron-hole pair (exciton), i.e. the building block of optoelectronic devices, is unique and not entirely understood so far.

Using advanced optical spectroscopies, we aim at exploring both the original electronic and excitonic band structures. We will address critical questions, such as: How do the electronic bands align in heterostructures of such materials? Does the excitonic band structure present the predicted light-like dispersion? Can we manipulate the spin and brightness of these materials by embedding them in an optical cavity?

Contacts :

published on April 23, 2018