by
Prof.Dimitri N. Basov(University of California San Diego)
→
Europe/Rome
Aula Conversi (Dipartimento di Fisica - Ed. G. Marconi)
Aula Conversi
Dipartimento di Fisica - Ed. G. Marconi
Description
The term plasmonics often carries an applied connotation
owing to remarkable successes in controlling and manipulating light at
the nanoscale in artificial structures. Infrared nano-spectroscopy and
nano-imaging experiments on graphene carried out in our group [Nano
Letters 11, 4701 (2011), Nature Nano 8, 821 (2013)] have uncovered a
rich variety of plasmonic effects that may enable functionalities not
attainable through metal-based plasmonics. Applications aside, the
nano-scale exploration of surface plasmons has offered an entirely new
perspective on fundamental physics behind electronic phenomena in
graphene. For example, by direct infrared imaging of plasmonic
standing waves we were able to quantify the electronic losses in
graphene [Nature 487, 82 (2012)]. This latter result highlights the
important role of many body effects that were not anticipated theoret!
ically. By examining the sub picosecond dynamics of plasmons in a
setting of a unique pump-probe nano-spectroscopy apparatus we were
able to discriminate between the roles of several photo-induced
processes in mono-layer and few layer graphene [under review].
Remarkably, infrared photo-excitation enables ultra-fast control of
plasmons with the efficiency rivaling that of electrostatic gating.
