You are here

Nano-photonic phenomena in van der Waals heterostructures

Speaker: 
D.N. Basov [University of California San Diego]
Date: 
Mon, 29/06/2015 - 11:00am to 12:00pm
Location: 
Physics Conference Room
Host: 
Antonio Castro Neto
Event Type: 
Seminars

Layered van der Waals (vdW) crystals, which consist of individual atomic planes weakly coupled by vdW interaction similar to graphene monolayers in solid graphite, can harbor remarkable properties: viz. superconductivity and ferromagnetism with high transition temperatures, light emission, and topologically protected surface states. Such artificial crystals provide building blocks for stacked heterostructures where each such block delivers layer-specific attributes. In examples assembled from atomically thin layers of graphene and hexagonal boron nitride (hBN), a rich variety of optical effects arise from the confluence of unusual elementary excitations: viz. surface plasmons in graphene and hyperbolic phonon polaritons in hBN. We have launched, detected and imaged plasmonic, phonon polaritonic and hybrid plasmon-phonon polariton waves in a setting of an antenna based nano-infrared apparatus. The nano-scale exploration of polaritonic modes has offered a new perspective on fundamental physics behind electronic phenomena in graphene. For example, by interferometric infrared imaging of plasmonic standing waves we were able to quantify the electronic losses in graphene. This latter result highlights the important role of many body effects  that were not anticipated theoretically.

 

Recent publications:

Fei et al. Nature 487, 82 (2012),

Basov et al. Reviews of Modern Physics 86, 959 (2014)

Dai et al Science 343, 1125 (2014).

Theme inspired by Danetsoft