Accessing the spectral function in a current-carrying device

DOI: 10.1103/PhysRevLett.125.236403

Authors: Davide Curcio (Aarhus University) , Alfred J. H. Jones (Aarhus University) , Ryan Muzzio (Carnegie Mellon University) , Klara Volckaert (Aarhus University) , Deepnarayan Biswas (Aarhus University) , Charlotte E. Sanders (Central Laser Facility, STFC Rutherford Appleton Laboratory) , Pavel Dudin (Diamond Light Source) , Cephise Cacho (Diamond Light Source) , Simranjeet Singh (Carnegie Mellon University) , Kenji Watanabe (National Institute for Materials Science, Tsukuba) , Takashi Taniguchi (National Institute for Materials Science, Tsukuba) , Jill A. Miwa (Aarhus University) , Jyoti Katoch (Carnegie Mellon University) , Soeren Ulstrup (Aarhus University) , Philip Hofmann (Aarhus University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review Letters , VOL 125

State: Published (Approved)
Published: December 2020
Diamond Proposal Number(s): 20218

Abstract: The presence of an electrical transport current in a material is one of the simplest and most important realizations of nonequilibrium physics. The current density breaks the crystalline symmetry and can give rise to dramatic phenomena, such as sliding charge density waves, insulator-to-metal transitions, or gap openings in topologically protected states. Almost nothing is known about how a current influences the electron spectral function, which characterizes most of the solid’s electronic, optical, and chemical properties. Here we show that angle-resolved photoemission spectroscopy with a nanoscale light spot provides not only a wealth of information on local equilibrium properties, but also opens the possibility to access the local nonequilibrium spectral function in the presence of a transport current. Unifying spectroscopic and transport measurements in this way allows simultaneous noninvasive local measurements of the composition, structure, many-body effects, and carrier mobility in the presence of high current densities. In the particular case of our graphene-based device, we are able to correlate the presence of structural defects with locally reduced carrier lifetimes in the spectral function and a locally reduced mobility with a spatial resolution of 500 nm.

Journal Keywords: Electrical conductivity; Electronic structure; Fermi surface; Transport phenomena; Angle-resolved photoemission spectroscopy

Subject Areas: Materials, Physics


Instruments: I05-ARPES

Added On: 04/01/2021 16:00

Discipline Tags:

Hard condensed matter - electronic properties Physics Materials Science

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES) Nano ARPES