[PAST EVENT] Physics Colloquium - Guangxin Ni

January 29, 2019
4pm - 5pm
Location
Small Hall, Room 111
300 Ukrop Way
Williamsburg, VA 23185Map this location
Access & Features
  • Open to the public

Guangxin Ni, Columbia University, Title of talk: Nano-light in van der Waals heterostructures

Abstract: Near-field nano-optics as a new and vibrant area of research has enabled the control and manipulation of electromagnetic radiations at the nano-meter length scales. In this talk, Dr. Ni will discuss recent nano-optical experiments on two-dimensional graphene/hexagonal boron nitride (G/hBN) van der Waals heterostructures. By harnessing infrared nano-optics one can directly image surface plasmon polaritonic standing waves and uncover its fundamental limits of graphene plasmonics [Nature (2018)]. The presence of periodic moir? patterns enables further fine tuning of the host materials and yielding rich insights into the electronic phenomenons. This has been manifested in both G/hBN moir? patterns [Nature Materials (2015)] and twisted bilayer graphene moir? structures [Science (2018)]. Furthermore, by examining the sub picosecond dynamics of plasmons in a unique set of pump-probe spectroscopy apparatus we were able to switch on plasmon on demand [Nature Photonics (2016)].