The first 2D topological insulator that consists of a single element

Nanowerk  May 16, 2023 The scattering of electrons at defects in 2D topological insulators is forbidden due to the unique topological protection mechanism which makes them more energy-efficient than current electronic materials. An international team of researchers (the Netherlands, Japan) made germanene was made from a single element. They melted germanium together with platinum. When the mixture cooled down, a tiny layer of germanium atoms arranged into a honeycomb lattice on top of the germanium-platinum alloy forming germanene. The conducting properties of the material could be switched ‘off’ by applying an electric field. This property is unique for a topological […]

At the water’s edge: Self-assembling 2D materials at a liquid-liquid interface

Science Daily  July 21, 2022 Researchers in Japan have demonstrated a facile one-pot synthesis of laminated 2D coordination polymer films comprising bis(terpyridine)iron and cobalt at a water/dichloromethane interface. Cross-sectional elemental mapping unveiled the stratum-like structure of the film and revealed that the second layer grows to the dichloromethane side below the first layer. Cyclic voltammetry clarified that the bottom layer mediates charge transfer between the top layer and the substrate in a narrow potential region of mixed-valence states. Furthermore, the bilayer film sandwiched by electrodes in a dry condition shows stable rectification character, and the barrier voltage corresponds to the […]

Scientists capture first-ever view of a hidden quantum phase in a 2D crystal

Phys.org  July 25, 2022 Nonequilibrium hidden states provide a unique window into thermally inaccessible regimes of strong coupling between microscopic degrees of freedom in quantum materials. However, mapping the ultrafast formation of a long-lived hidden phase remains a longstanding challenge since the initial state is not recovered rapidly. Using state-of-the-art single-shot spectroscopy techniques, a team of researchers in the US (MIT, Harvard University, UT Austin) has realized a direct ultrafast visualization of the photoinduced phase transition to both transient and long-lived hidden states in an electronic crystal, 1T-TaS2, and demonstrated a commonality in their microscopic pathways, driven by the collapse […]