Blog
- Electronic self-passivation of single vacancy in black phosphorus 07/06/2022 NUS scientists discovered that a two-dimensional (2D) semiconducting material, known as black phosphorus (BP), exhibits an electronic self-passivation phenomenon by re-arranging its vacancy defects. This may potentially enhance the charge mobility of the material and its analogs.
- Collaboration reveals interplay between charge order and superconductivity at nanoscale 02/06/2022 High temperature superconductivity is something of a holy grail for researchers studying quantum materials. Superconductors, which conduct electricity without dissipating energy, promise to revolutionize our energy and telecommunication power systems. However, superconductors typically work at extremely low temperatures, requiring elaborate freezers or expensive coolants. For this reason, scientist have been relentlessly working on understanding the fundamental mechanisms at the base of high-temperature superconductivity with the ultimate goal to design and engineer new quantum materials superconducting close to room temperature.
- Ultrahigh piezoelectric performance demonstrated in ceramic materials 31/05/2022 The ability of piezoelectric materials to convert mechanical energy into electrical energy and vice versa makes them useful for various applications from robotics to communication to sensors. A new design strategy for creating ultrahigh-performing piezoelectric ceramics opens the door to even more beneficial uses for these materials, according to a team of researchers from Penn State and Michigan Technological University.
- Researchers develop new measurement method in molecular electronics 26/05/2022 In molecular electronics, single molecules are stretched between two electrodes to form an electrically conducting element in which molecular conductivity is then measured. Although the underlying method for this phenomenon, scanning tunneling microscopy, was awarded the Nobel Prize more than thirty years ago, a major limitation remains: To access molecular conductivity, the molecules to be measured had to be permanently attached to the inorganic gold electrodes, usually via sulfur bridges.
- Periodic Nanoarray of Graphene pn-Junctions on Silicon Carbide Obtained by Hydrogen Intercalation 24/05/2022 Graphene pn-junctions offer a rich portfolio of intriguing physical phenomena. They stand as the potential building blocks for a broad spectrum of future technologies, ranging from electronic lenses analogous to metamaterials in optics, to high-performance photodetectors important for a variety of optoelectronic applications. The production of graphene pn-junctions and their precise structuring at the nanoscale remains to be a challenge. In this work, a scalable method for fabricating periodic nanoarrays of graphene pn-junctions on a technologically viable semiconducting SiC substrate is introduced. Via H-intercalation, 1D confined armchair graphene nanoribbons are transformed into a single 2D graphene sheet rolling over 6H-SiC mesa structures. Due to the different surface terminations of the basal and vicinal SiC planes constituting the mesa structures, different types of charge carriers are locally induced into the graphene layer. Using angle-resolved photoelectron spectroscopy, the electronic band structure of the two graphene regions are selectively measured, finding two symmetrically doped phases with p-type being located on the basal planes and n-type on the facets. The results demonstrate that through a careful structuring of the substrate, combined with H-intercalation, integrated networks of graphene pn-junctions could be engineered at the nanoscale, paving the way for the realization of novel optoelectronic device concepts.
- Assessing the impact of loss mechanisms in solar cell candidate antimony sulfide selenide 19/05/2022 As climate change continues to present itself as the most pressing threat facing our planet, researchers push to find efficient and clean alternatives to fossil fuels. Foremost among this research is harnessing free energy from the sun. Doing this efficiently requires advanced knowledge of the qualities of materials used in the construction of solar cells.
- Non-invasive imaging of atomic arrangement at the sub-angstrom scale in 2-D hybrid perovskites 17/05/2022 Materials scientists aim to identify the atomic arrangement of 2D Ruddlesden-Popper hybrid perovskites (RPP) using non-invasive imaging; however, the process is challenging due to the insulating nature and softness of the organic layers.
- From conventional to strange metal behavior in magic-angle twisted bilayer graphene 12/05/2022 Magic-angle twisted bilayer graphene (MATBG) is a graphene-based material with a unique structure, consisting of two graphene sheets layered on top of each other with a misalignment of approximately 1.1°. This unique structure has been found to host various interesting states, including correlated insulating states and unconventional superconductivity.
- Beyond van der Waals: The next generation of covalent 2D-2D heterostructures 10/05/2022 A team of scientists have "velcroed" 2D structures of MoS2 and graphene using a covalent connection for the first time. The 2D-2D structures were used to build robust field effect transistors with controlled electronic communication, interface chemical nature and interlayer distance.
- Skyrmions on the rise: New 2D material advances low-power computing 05/05/2022 Two-dimensional magnetic materials have been hailed as building blocks for the next generation of small, fast electronic devices. These materials, made of layers of crystalline sheets just a few atoms thick, gain their unique magnetic properties from the intrinsic compass-needle-like spins of their electrons. The sheets' atomic-scale thinness means that these spins can be manipulated on the finest scales using external electric fields, potentially leading to novel low-energy data storage and information processing systems. But knowing exactly how to design 2D materials with specific magnetic properties that can be precisely manipulated remains a barrier to their application.
- Lasers trigger magnetism in atomically thin quantum materials 03/05/2022 Researchers have discovered that light—in the form of a laser—can trigger a form of magnetism in a normally nonmagnetic material. This magnetism centers on the behavior of electrons. These subatomic particles have an electronic property called "spin," which has a potential application in quantum computing. The researchers found that electrons within the material became oriented in the same direction when illuminated by photons from a laser.