Physics Colloquium: Live from New York: Polaritons in van der Waals Materials
Prof. Dmitri Basov, Columbia University
In 1944 Hans Bethe reported on “the diffraction of electromagnetic radiation by a hole small compared with the wave-length” [Physical Review 66, 163 (1944)]. This seminal paper was among the early precursors to a new and vibrant area of research: near field nano-optics. I will discuss recent nano-optical experiments on quantum materials including graphene and other atomically layered crystals. Central to the nano-optical exploration of quantum materials is the notion of polaritons: hybrid light-matter modes that are omnipresent in polarizable media [Science 354, 195 (2016)]. Ballistic plasmon polaritons in graphene [Nature 557, 530 (2018)] have allowed us to investigate the Fizeau drag in solids. The Fizeau experiment: light dragging by moving water is a cornerstone of special relativity. Experiments on dragging photons by an electron flow in solids continued throughout all of the 20-th century. However, these data remain riddled with inconsistencies and so far eluded agreement with the theory. I will report on the new data providing an unambiguous experimental demonstration of electrical control of Fizeau dragging effect by exploiting polaritons formed by Dirac electrons in graphene.
Event Organizer: Prof. Haim Suchowski