CM Seminar - Doping a Mott Insulator and Unconventional Superconductivity in a Triangular Adatom Layer on a Silicon Surface

22 Oct2020

Speaker: Steve Johnston, Professor at University of Tennessee, Knoxville

Time: October 22, 2020 : 2:00PM - 3:00PM

Location:

Canada

https://ubc.zoom.us/j/65784122083?pwd=U09vVXJMRzNLaTY3bmVXNEFJZ1k3UT09
Meeting ID: 657 8412 2083
Passcode: 113399

Abstract: The physics of doped Mott insulators is at the heart of some of the most exotic physical phenomena in materials research. The adsorption of a one-third monolayer of Sn atoms on a Si(111) surface produces a triangular surface lattice with half-filled dangling bond orbitals. In this talk, I will show how modulation hole doping of these dangling bonds unveils clear hallmarks of Mott physics [1], including a spectral weight transfer and the formation of dispersive quasiparticles at the Fermi level. I will also discuss the recent observation of superconductivity [2] in the most heavily hole-doped monolayers and evidence for an unconventional d+id chiral order parameter. These observations are remarkably similar to those made in complex oxide materials, including high-temperature superconductors, but highly extraordinary within the realm of conventional sp-bonded semiconductor materials. 

  • Seminar