Manifold learning of four-dimensional scanning transmission electron microscopy

Four-dimensional scanning transmission electron microscopy(4D-STEM)of local atomic diffraction patterns is emerging as a powerful technique for probing intricate details of atomic structure and atomic electric fields.However,efficient processing and interpretation of large volumes of data remain challenging,especially for two-dimensional or light materials because the diffraction signal recorded on the pixelated arrays is weak.Here we employ data-driven manifold leaning approaches for straightforward visualization and exploration analysis of 4D-STEM datasets,distilling real-space neighboring effects on atomically resolved deflection patterns from single-layer graphene,with single dopant atoms,as recorded on a pixelated detector.These extracted patterns relate to both individual atom sites and sublattice structures,effectively discriminating single dopant anomalies via multimode views.We believe manifold learning analysis will accelerate physics discoveries coupled between data-rich imaging mechanisms and materials such as ferroelectric,topological spin,and van der Waals heterostructures.

Localised solid-state nanopore fabrication via controlled breakdown using on-chip electrodes

Controlled breakdown has recently emerged as a highly accessible technique to fabricate solid-state nanopores.However,in its most common form,controlled breakdown creates a single nanopore at an arbitrary location in the membrane.Here,we introduce a new strategy whereby breakdown is performed by applying the electric field between an on-chip electrode and an electrolyte solution in contact with the opposite side of the membrane.We demonstrate two advantages of this method.First,we can independently fabricate multiple nanopores at given positions in the membrane by localising the applied field to the electrode.Second,we can create nanopores that are self-aligned with complementary nanoelectrodes by applying voltages to the on-chip electrodes to locally heat the membrane during controlled breakdown.This new controlled breakdown method provides a path towards the affordable,rapid,and automatable fabrication of arrays of nanopores self-aligned with complementary on-chip nanostructures.

Author Correction:Manifold learning of four-dimensional scanning transmission electron microscopy

The original version of the published Article had a mistake in the Acknowledgements section.The Acknowledgments have been updated to the following:This research was supported by the US Department of Energy,Basic Energy Sciences,Materials Sciences and Engineering Division(M.P.O.,A.R.L.,S.V.K.)and conducted at the Center for Nanophase Materials Sciences,which is a US DOE Office of Science User Facility(X.L.,O.E.D.,S.J.).L.M.and J.H.acknowledge support from Tutte Institute for Mathematics and Computing,Canada.