Eric LE MOAL, from ISMO, will give a talk in Pierre Cotton’s room entitled “Widefield optical microscopy of tip-induced electroluminescence in 2D materials” on Tuesday November 10th at 02:00 p.m.
Abstract: The scanning tunneling microscope (STM) is not only a surface science tool capable of producing atomically resolved images of crystalline surfaces; it is also an extraordinary instrument for nano-optics. The inelastic tunneling current between the STM tip and the sample surface leads to extremely localized excitation of existing optical modes. Thus, the tip-sample junction can behave as a nanosource of photons, plasmons, or excitons, depending on the nature of the sample. In this presentation, I will discuss research that demonstrates the potential of integrating an STM with an optical microscope to study electron-exciton interactions in atomically thin semiconductor materials (i.e., monolayers of transition metal dichalcogenides). More precisely, we combine highly localized excitation under the STM tip with wide-field optical microscopy (to image the spatial distribution of the emission) and deconvolution of the optical images using the iterative Richardson-Lucy algorithm (to achieve spatial resolution beyond the diffraction limit). This approach sheds light on the role of charge-carrier and exciton transport in the electroluminescence properties of these materials.
The seminar is open to everybody. Looking forward to seeing you there.
Contact: Eric LE MOAL, CNRS researcher at ISMO, Nanophysics & Surfaces Team
Organization: Jérôme Wenger, Loïc Le Goff or Guillaume Baffou
