In‐operando NanoARPES: Spatial mapping of the electronic structure of twisted bilayer graphene

DOI: 10.1002/smsc.202000075

Authors: Paulina Majchrzak (Aarhus University) , Ryan Muzzio (Carnegie Mellon University) , Alfred J. H. Jones (Aarhus University) , Davide Curcio (Aarhus University) , Klara Volckaert (Aarhus University) , Deepnarayan Biswas (Aarhus University) , Jacob Gobbo (Carnegie Mellon University) , Simranjeet Singh (Carnegie Mellon University) , Jeremy T. Robinson (US Naval Research Laboratory) , Kenji Watanabe (National Institute for Materials Science, Japan) , Takashi Taniguchi (National Institute for Materials Science, Japan) , Timur K. Kim (Diamond Light Source) , Cephise Cacho (Diamond Light Source) , Jill A. Miwa (Aarhus University) , Philip Hofmann (Aarhus University) , Jyoti Katoch (Carnegie Mellon University) , Soeren Ulstrup (Aarhus University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Small Science

State: Published (Approved)
Published: March 2021
Diamond Proposal Number(s): 24072

Abstract: To pinpoint the electronic and structural mechanisms that affect intrinsic and extrinsic performance limits of two‐dimensional material devices, it is of critical importance to resolve the electronic properties on the mesoscopic length scale of such devices under operating conditions. The present work utilizes angle‐resolved photoemission spectroscopy with nanoscale spatial resolution (nanoARPES) to map the quasiparticle electronic structure of a twisted bilayer graphene device. The dispersion and linewidth of the Dirac cones associated with top and bottom graphene layers are determined as a function of spatial position on the device under both static and operating conditions. The analysis reveals that microscopic rotational domains in the two graphene layers establish a range of twist angles from 9.8∘ to 12.7∘. Application of current and electrostatic gating lead to strong electric fields with peak strengths of 0.75 V/μm at the rotational domain boundaries in the device. These proof‐of‐principle results demonstrate the potential of nanoARPES to link mesoscale structural variations with electronic states in operating device conditions and to disentangle such extrinsic factors from the intrinsic quasiparticle dispersion.

Journal Keywords: 2D material device; electron transport; nanoARPES; twisted bilayer graphene; Van der Waals heterostructure

Subject Areas: Materials, Physics, Technique Development


Instruments: I05-ARPES

Added On: 18/03/2021 08:28

Documents:
smsc.202000075.pdf

Discipline Tags:

Quantum Materials Physics Technique Development - Physics Materials Science

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES) Nano ARPES