Electron-electron interactions play a critical role in many condensed matter phenomena, and it is tempting to find a way to control them by changing the interactions' strength. One possible approach is to place a studied system in proximity of a metal, which induces additional screening and hence suppresses electron interactions. Here, using devices with atomically-thin gate dielectrics and atomically-flat metallic gates, we measure the electron-electron scattering length in graphene and report qualitative deviations from the standard behavior. The changes induced by screening become important only at gate dielectric thicknesses of a few nm, much smaller than a typical separation between electrons. Our theoretical analysis agrees well with the scattering rates extracted from measurements of electron viscosity in monolayer graphene and of umklapp electron-electron scattering in graphene superlattices. The results provide a guidance for future attempts to achieve proximity screening of many-body phenomena in two-dimensional systems.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7214472 | PMC |
| http://dx.doi.org/10.1038/s41467-020-15829-1 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Structure and dynamics of monoclonal antibody domains determined using spins, scattering, and simulations.
ChemMedChem
January 2025
National Institute of Standards and Technology, Material Measurement Laboratory, UNITED STATES OF AMERICA.
Antibody-based pharmaceuticals are the leading biologic drug platform (> $75B/year). Despite a wealth of information collected on them, there is still a lack of knowledge on their inter-domain structural distributions, which impedes innovation and development. To address this measurement gap, we have developed a new methodology to derive biomolecular structure ensembles from distance distribution measurements via a library of tagged proteins bound to an unlabeled and otherwise unmodified target biologic.
View Article and Find Full Text PDFTerahertz Saturable Absorption across Charge Separation in Photoexcited Monolayer Graphene/MoS Heterostructure.
J Phys Chem Lett
January 2025
Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China.
Unveiling the nonlinear interactions between terahertz (THz) electromagnetic waves and free carriers in two-dimensional materials is crucial for the development of high-field and high-frequency electronic devices. Herein, we investigate THz nonlinear transport dynamics in a monolayer graphene/MoS heterostructure using time-resolved THz spectroscopy with intense THz pulses as the probe. Following ultrafast photoexcitation, the interfacial charge transfer establishes a nonequilibrium carrier redistribution, leaving free holes in the graphene and trapping electrons in the MoS.
View Article and Find Full Text PDFAnti-Poiseuille flow by spin Hall effect.
PNAS Nexus
December 2024
RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan.
Hydrodynamics is known to emerge in electron flow when the electron-electron interaction dominates over the other momentum-nonconserving scatterings. The hydrodynamic equation that describes the electric current includes viscosity, extending beyond the Ohmic flow. The laminar flow of such a viscous electron fluid in a sample with finite width is referred to as the Poiseuille flow, where the flow velocity is maximum at the center and decreases towards the edges of the sample.
View Article and Find Full Text PDFResonant third-harmonic generation driven by out-of-equilibrium electron dynamics in sodium-based near-zero index thin films.
Nanophotonics
May 2024
Department of Physical and Chemical Sciences, University of L'Aquila, Via Vetoio, 67100 L'Aquila, Italy.
We investigate resonant third-harmonic generation in near-zero index thin films driven out-of-equilibrium by intense optical excitation. Adopting the Landau weak coupling formalism to incorporate electron-electron and electron-phonon scattering processes, we derive a novel set of hydrodynamic equations accounting for collision-driven nonlinear dynamics in sodium. By perturbatively solving hydrodynamic equations, we model third-harmonic generation by a thin sodium film, finding that such a nonlinear process is resonant at the near-zero index resonance of the third-harmonic signal.
View Article and Find Full Text PDFSpin Dynamics in Hybrid Halide Perovskites - Effect of Dynamical and Permanent Symmetry Breaking.
J Phys Chem Lett
December 2024
Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
The hybrid organic-inorganic halide perovskite (HOIP), for example, MAPbBr, exhibits extended spin lifetime and apparent spin lifetime anisotropy in experiments. The underlying mechanisms of these phenomena remain illusive. By utilizing our first-principles density-matrix dynamics approach with quantum scatterings including electron-phonon and electron-electron interactions and self-consistent spin-orbit coupling, we present temperature- and magnetic field-dependent spin lifetimes in hybrid perovskites, in agreement with experimental observations.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!