Van der Waals Metamaterials
Date: Tuesday, Nov. 17
Time: 3:10 pm
Place: SST 106
Speaker: Prof. Dimitri Basov
Title: Van der Waals Metamaterials
Metamaterials are artificial structures engineered to have properties that have not yet been found in nature.
Electromagnetic metamaterials enabled a myriad of non-intuitive optical phenomena including negative refractive index, super-lensing and invisibility. Our group has proposed a novel approach for realization of broadly tunable metamaterials by exploiting the interaction of distinct types of polaritonic modes hosted by different constituent layers of van der Waals heterostructures [Dai et al. Nature Nanotechnology 10, 682 (2015)]. We have implemented and investigated the tunable hyperbolic response in heterostructures comprised of a monolayer graphene deposited on hexagonal boron nitride (G-hBN) slabs.
Electrostatic gating of the graphene layer enables electronic tunability of phonon polaritonic properties of
hBN: a layered material with well-documented hyperbolic response in the mid-infrared frequencies [Dai et al. Science 343, 1125 (2014)]. The hybrid polaritons possess combined virtues from plasmons in graphene and phonon polaritons in hBN.