van der Waals Interactions and Wetting of Graphene

Speaker: 
Valeri Kotov
Institution: 
University of Vermont
Date: 
Monday, June 5, 2017
Time: 
11:00 am
Location: 
NS2 1201

* Special Day / Time

Abstract:  

I will discuss van der Waals (VDW) interactions between neutral atoms such as He, H, and Na) and Graphene. VDW forces are quite sensitive to graphene’s electronic spectrum, electron-electron interactions, as well as various external factors that can influence those, such as strain. I will describe the role VDW interactions play in elastic scattering phenomena, most notably in determining the quantum reflection (QR) coefficient for cold atoms interacting (via VDW) with graphene.

 

In the second part of my talk I will discuss collective phenomena driven by VDW forces. For example formation and growth of thin liquid films on solid substrates is determined by VDW interactions. I will show (using the so-called Lifshitz theory) that the presence of atomically thin material, such as graphene, on top of a conventional substrate can have profound effect on liquid film growth. Most importantly, for suspended graphene we find that film growth can become arrested at a critical thickness. This may lead to novel types of wetting instabilities, similar to “spinodal dewetting.”

Host: 
Sasha Chernyshev