Type: 
SSO Seminar
Date-Time: 
Wednesday, October 11, 2017 - 16:00 to 17:00
Location: 
304 Weniger
Event Speaker: 
Ethan Minot
Local Contact: 
David McIntyre
Abstract: 

Strong electron-electron (e-e) interactions play an important role in determining the electrical and optical properties of nanomaterials. Our group uses individually-contacted carbon nanotubes (CNTs) as a model experimental system to investigate the physics and applications of these strong interactions. I will discuss: (1) The quantum efficiency of CNT photodiodes,1 (2) renormalization of the band gap in semiconducting CNTs,2 (3) the emergence of a Mott insulating state in metallic CNTs. All three of these topics depend critically on the strength of e-e interactions which we tune experimentally using dielectric screening. We also gain new insights by using photocurrent spectroscopy to precisely identify CNT diameter/chirality, and photocurrent microscopy to quantify intrinsic region lengths.

 

1 Aspitarte, McCulley, Minot,  “Photocurrent Quantum Yield in Suspended Carbon Nanotube PN Junctions” Nano Letters 16, 5589  (2016)

2 Aspitarte, McCulley, Bertoni, Island, Ostermann, Rontani, Steele & Minot, “Giant modulation of the electronic band gap of carbon nanotubes by dielectric screening”, Scientific Reports 7, 8828 (2017)