Event

Layered van der Waals (vdW) crystals consist of individual atomic planes weakly coupled by vdW interaction, similar to graphene monolayers in bulk graphite. These materials can harbor superconductivity and ferromagnetism with high transition temperatures, emit light and exhibit topologically protected surface states. An ambitious practical goal is to exploit atomic planes of vdW crystals as building blocks of more complex artificially stacked heterostructures where each such block will deliver layer-specific attributes for the purpose of their combined functionality. We investigated van der Waals heterostructures assembled from atomically thin layers of graphene and hexagonal boron nitride (hBN). We observed a rich variety of optical effects due to surface plasmons in graphene [Reviews of Modern Physics 86, 959 (2014)] and hyperbolic phonon polaritons in hBN [Science 343, 1125 (2014)]. We launched, detected and imaged plasmonic, phonon polaritonic and hybrid plasmon-phonon polariton waves in a setting of an antenna based nano-infrared apparatus [Nature 487, 82 (2012)]. The nano-scale exploration of surface plasmons has offered an entirely new perspective on fundamental physics behind electronic phenomena in graphene [Nature Materials 14, 1217 (2015), Nature Nano 10, 682 (2015)]. I will also discuss an ability to manipulate the plasmonic response of these structures at femto second time scales that we have demonstrated using a novel technique of pump-probe nano-infrared spectroscopy [Nature Photonics (2016)].

Dmitri N. Basov (PhD 1991, Russian Academy of Sciences) is a professor (since 1997) and Chair (2010-15) of Physics, University of California San Diego. Research interests include: physics of correlated electron systems, superconductivity, two-dimensional materials, infrared nano-optics. Prizes and awards: Sloan Fellowship (1999), Genzel Prize (2014), Humboldt research award (2009), Frank Isakson Prize, American Physical Society (2012), Moore Investigator (2014).

UCSD http://infrared.ucsd.edu