Anomalous Dynamical Behavior of Freestanding Graphene Membranes

TL;DR

This paper presents high-resolution measurements of freestanding graphene's vertical motion, revealing rare long-scale excursions with anomalous dynamics, achieved through advanced scanning tunneling microscopy.

Contribution

It introduces a novel high-bandwidth measurement technique enabling detailed observation of graphene's out-of-plane atomic motion over extended periods.

Findings

Observed rare long-scale excursions in graphene vertical motion

Detected anomalous mean-squared displacements

Identified Cauchy-Lorentz power law jump distributions

Abstract

We report subnanometer, high-bandwidth measurements of the out-of-plane (vertical) motion of atoms in freestanding graphene using scanning tunneling microscopy. By tracking the vertical position over a long time period, a 1000-fold increase in the ability to measure space-time dynamics of atomically thin membranes is achieved over the current state-of-the-art imaging technologies. We observe that the vertical motion of a graphene membrane exhibits rare long-scale excursions characterized by both anomalous mean-squared displacements and Cauchy-Lorentz power law jump distributions.