Past Events

In a first part of the talk, we discuss atomically thin materials as a robust platform for manipulating light at the nanoscale thanks to a wide variety of polaritonic modes, ranging from plasmons in thin metals and doped graphene to excitons in transition metal dichalcogenides and phonons in ionic insulators. The electromagnetic behavior of these modes can be well understood in terms of effective surface conductivities with simple theoretical models. We also discuss more sophisticated models, aiming at the exploration of genuinely quantum-mechanical effects. We further review recent advances in the control of ultrafast and nonlinear optical processes, as well as potential applications in light modulation and quantum-optics. We propose innovative solutions based on critical coupling between dipolar scatterers and planar interfaces to tackle in/out coupling problem. We further discuss a disruptive approach to the design of polaritonic materials relying on quantum phase effects, as well as a new mechanism of electron-positron pair production based on the scattering between gamma-rays and surface polaritons

 

In a second part of the talk, we will focus on free electrons as tools that allow us to sample and modify quantum optical fields. Thanks to recent advancements in electron microscope technology and the manipulation of free electrons, including the synthesis of femtosecond electron wave packets that are synchronized with femtosecond light pulses, we are now able to control the wave functions of free electrons and their interaction with nanoscale optical excitations. In this presentation, we will offer an overview of the fundamental principles ruling the interactions between free electrons, light, and photonic nanostructures. We will place particular emphasis on exploring the quantum aspects of these interactions, and discuss potential applications such as noninvasive spectroscopy and microscopy, optical manipulation of electron beams, and the development of improved techniques for generating electron-induced light emission.

 

Biography

Javier García de Abajo received his PhD from the University of the Basque Country (1993) and then visited Berkeley National Lab for three years. He was a Research Professor at the Spanish Research Council and in 2013 moved to ICFO-Institut de Ciencies Fotoniques (Barcelona) as an ICREA Research Professor and Group Leader. He is a Fellow of both the American Physical Society and the Optical Society of America. García de Abajo has co-authored 400+ articles cited 60,000+ times with an h index of 118 (Google Scholar), including contributions on different aspects of surface science, nanophotonics, and electron microscope spectroscopies.