Center for Artificial Low Dimensional Electronic Systems

Probing Electronic Properties of Two-Dimensional Materials with Planar Tunnel Junctions

Suyong Jung

March 24(Fri) - March 24(Fri), 2017

Probing Electronic Properties of Two-Dimensional Materials

with Planar Tunnel Junctions

Suyong Jung

Korea Research Institute of Standards and Science

Two-dimensional van der Waals heterostructures utilizing thin hexagonal boron nitride (h-BN) as a tunneling insulator have been proven as interesting experimental platforms for investigating electronic structures of low-dimensional systems.  Here we present electron tunneling spectroscopy measurements on various two-dimensional electronic systems comprised of graphene, h-BN, and transition metal dichalcogenides.  With much improved tunnel junction stability of thin h-BN insulator, we can probe the electronic structures of two-dimensional systems such as Landau levels in graphene, energy gaps in bilayer graphene, secondary minibands formed in graphene superlattice and superconductivity in NbSe₂ with much improved signal-to-noise ratio by varying charge density, tunneling bias voltage and external magnetic fields. We will discuss the current understanding of the observed phenomena and discuss future research plans with planar tunnel junctions.