Supramolecular Assembly of Fused Macrocycle-Cage Molecules for Fast Lithium-Ion Transport.

We report a new supramolecular porous crystal assembled from fused macrocycle-cage molecules. The molecule comprises a prismatic cage with three macrocycles radially attached. The molecules form a nanoporous crystal with one-dimensional (1D) nanochannels.

In operando cryo-STEM of pulse-induced charge density wave switching in TaS.

The charge density wave material 1T-TaS exhibits a pulse-induced insulator-to-metal transition, which shows promise for next-generation electronics such as memristive memory and neuromorphic hardware. However, the rational design of TaS devices is hindered by a poor understanding of the switching mechanism, the pulse-induced phase, and the influence of material defects. Here, we operate a 2-terminal TaS device within a scanning transmission electron microscope at cryogenic temperature, and directly visualize the changing charge density wave structure with nanoscale spatial resolution and down to 300 μs temporal resolution.

Accuracy of Local Polarization Measurements by Scanning Transmission Electron Microscopy.

Accurately determining local polarization at atomic resolution can unveil the mechanisms by which static and dynamical behaviors of the polarization occur, including domain wall motion, defect interaction, and switching mechanisms, advancing us toward the better control of polarized states in materials. In this work, we explore the potential of atomic-resolution scanning transmission electron microscopy to measure the projected local polarization at the unit cell length scale. ZnO and PbMgNbO are selected as case studies, to identify microscope parameters that can significantly affect the accuracy of the measured projected polarization vector.