Full momentum- and energy-resolved spectral function of a 2D electronic system

The single-particle spectral function measures the density of electronic states in a material as a function of both momentum and energy, providing central insights into strongly correlated electron phenomena. Here we demonstrate a high-resolution method for measuring the full momentum- and energy-re...

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Bibliographic Details
Main Authors: Pfeiffer, L. N., West, K. W., Baldwin, K. W., Jang, Joonho, Yoo, Heun Mo, Ashoori, Raymond
Other Authors: Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Format: Article
Published: American Association for the Advancement of Science (AAAS) 2019
Online Access:http://hdl.handle.net/1721.1/121033
https://orcid.org/0000-0003-4380-102X
https://orcid.org/0000-0001-8842-0154
https://orcid.org/0000-0001-5031-1673
Description
Summary:The single-particle spectral function measures the density of electronic states in a material as a function of both momentum and energy, providing central insights into strongly correlated electron phenomena. Here we demonstrate a high-resolution method for measuring the full momentum- and energy-resolved electronic spectral function of a two-dimensional (2D) electronic system embedded in a semiconductor. The technique remains operational in the presence of large externally applied magnetic fields and functions even for electronic systems with zero electrical conductivity or with zero electron density. Using the technique on a prototypical 2D system, a GaAs quantum well, we uncover signatures of many-body effects involving electron-phonon interactions, plasmons, polarons, and a phonon analog of the vacuum Rabi splitting in atomic systems.