Dielectric disorder in two-dimensional materials
Artikel i vetenskaplig tidskrift, 2019
Understanding and controlling disorder is key to nanotechnology and materials science. Traditionally, disorder is attributed to local fluctuations of inherent material properties such as chemical and structural composition, doping or strain. Here, we present a fundamentally new source of disorder in nanoscale systems that is based entirely on the local changes of the Coulomb interaction due to fluctuations of the external dielectric environment. Using two-dimensional semiconductors as prototypes, we experimentally monitor dielectric disorder by probing the statistics and correlations of the exciton resonances, and theoretically analyse the influence of external screening and phonon scattering. Even moderate fluctuations of the dielectric environment are shown to induce large variations of the bandgap and exciton binding energies up to the 100 meV range, often making it a dominant source of inhomogeneities. As a consequence, dielectric disorder has strong implications for both the optical and transport properties of nanoscale materials and their heterostructures.
Författare
A. Raja
Lawrence Berkeley National Laboratory
University of California
Lutz Waldecker
Stanford University
Jonas Zipfel
Universität Regensburg
Yeongsu Cho
University of Chicago
Samuel Brem
Chalmers, Fysik, Kondenserade materiens teori
Jonas D. Ziegler
Universität Regensburg
Marvin Kulig
Universität Regensburg
Takashi Taniguchi
National Institute for Materials Science (NIMS)
Kenji Watanabe
National Institute for Materials Science (NIMS)
Ermin Malic
Chalmers, Fysik, Kondenserade materiens teori
T. F. Heinz
Stanford University
Timothy C. Berkelbach
Flatiron Institute
Columbia University
A. Chernikov
Universität Regensburg
Nature Nanotechnology
1748-3387 (ISSN) 1748-3395 (eISSN)
Vol. 14 9 832-837Ämneskategorier
Annan kemi
Annan materialteknik
Den kondenserade materiens fysik
DOI
10.1038/s41565-019-0520-0