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A research team led by a physicist at the University of California, Riverside, has demonstrated a new magnetized state in a monolayer of tungsten ditelluride, or WTe₂, a new quantum material. Called a magnetized or ferromagnetic quantum spin Hall insulator, this material of one-atom thickness has an insulating interior but a conducting edge, which has important implications for controlling electron flow in nanodevices.

In a typical conductor, electrical current flows evenly everywhere. Insulators, on the other hand, do not readily conduct electricity. Ordinarily, monolayer WTe₂ is a special insulator with a conducting edge; magnetizing it bestows upon it more unusual properties.

“We stacked monolayer WTe₂ with an insulating ferromagnet of several atomic layer thickness—of Cr₂Ge₂Te₆, or simply CGT—and found that the WTe₂ had developed ferromagnetism with a conducting edge,” said Jing Shi, a distinguished professor of physics and astronomy at UCR, who led the study. “The edge flow of the electrons is unidirectional and can be made to switch directions with the use of an external magnetic field.”

In a recent publication in the journal Advanced Materials, a team of physicists and chemists from TU Dresden presents an organic thin-film sensor that describes a completely new way of identifying the wavelength of light and achieves a spectral resolution below one nanometer. As integrated components, the thin-film sensors could eliminate the need for external spectrometers in the future. A patent application has already been filed for the novel technology.

Spectroscopy comprises a group of experimental methods that decompose radiation according to a specific property, such as wavelength or mass. It is considered one of the most important analytical methods in research and industry. Spectrometers can determine colors (wavelengths) of light sources and are used as sensors in various applications, such as medicine, engineering, food industry and many more. Commercially available instruments are usually relatively large and very expensive. They are mostly based on the principle of the prism or grating: light is refracted and the wavelength is assigned according to the angle of refraction.

At the Institute for Applied Physics (IAP) and the Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) of the TU Dresden, such sensor components based on organic semiconductors have been researched for years. With the spin-offs Senorics and PRUUVE, two technologies have already been developed towards market maturity. Now, researchers at the IAP and IAPP, in cooperation with the Institute of Physical Chemistry, have developed a thin-film sensor that describes a completely new way of identifying the wavelength of light and, due to its small size and cost, has clear advantages over commercially available spectrometers.

Squeaky, cloudy or spherical—electron orbitals show where and how electrons move around atomic nuclei and molecules. In modern chemistry and physics, they have proven to be a useful model for quantum mechanical description and prediction of chemical reactions. Only if the orbitals match in space and energy can they be combined—this is what happens when two substances react with each other chemically. In addition, there is another condition that must be met, as researchers at Forschungszentrum Jülich and the University of Graz have now discovered: The course of chemical reactions also appears to be dependent on the orbital distribution in momentum space. The results were published in the journal Nature Communications.

Chemical reactions are ultimately nothing more than the formation and breakdown of electron bonds, which can also be described as orbitals. The so-called molecular orbital theory thus makes it possible to predict the path of chemical reactions. Chemists Kenichi Fukui and Roald Hoffmann received the Nobel Prize in 1981 for greatly simplifying the method, which led to its widespread use and application.

“Usually, the energy and location of electrons are analyzed. However, using the photoemission tomography method, we looked at the momentum distribution of the orbitals,” explains Dr. Serguei Soubatch. Together with his colleagues at the Peter Grünberg Institute (PGI-3) in Jülich and the University of Graz in Austria, he adsorbed various types of molecules on metal surfaces in a series of experiments and mapped the measured momentum in the so-called momentum space.

Two-dimensional van der Waals materials have been the focus of work by numerous research groups for some time. Standing just a few atomic layers thick, these structures are produced in the laboratory by combining atom-thick layers of different materials (in a process referred to as “atomic Lego”). Interactions between the stacked layers allow the heterostructures to exhibit properties that the individual constituents lack.

Two-layered molybdenum disulfide is one such van der Waals material, in which electrons can be excited using a suitable experimental setup. These negatively charged particles then leave their position in the valence band, leaving behind a positively charged hole, and enter the conduction band. Given the different charges of electrons and holes, the two are attracted to one another and form what is known as a quasiparticle. The latter is also referred to as an electron-hole pair, or exciton, and can move freely within the material.

In two-layered molybdenum disulfide, excitation with light produces two different types of electron-hole pairs: intralayer pairs, in which the electron and hole are localized in the same layer of the material, and interlayer pairs, whose hole and electron are located in different layers and are therefore spatially separate from one another.

Researchers discovered a private Telegram channel-based backdoor in the information stealing malware, dubbed Prynt Stealer, which its developer added with the intention of secretly stealing a copy of victims’ exfiltrated data when used by other cybercriminals.

“While this untrustworthy behavior is nothing new in the world of cybercrime, the victims’ data end up in the hands of multiple threat actors, increasing the risks of one or more large scale attacks to follow,” Zscaler ThreatLabz researchers Atinderpal Singh and Brett Stone-Gross said in a new report.

Prynt Stealer, which came to light earlier this April, comes with capabilities to log keystrokes, steal credentials from web browsers, and siphon data from Discord and Telegram. It’s sold for $100 for a one-month license and $900 for a lifetime subscription.

TikTok has denied reports of a data breach after a hacker group claimed to have gained access to information on two billion of its users.

Ransomware hackers are abusing an anti-cheat system driver for the extremely popular game Genshin Impact to disable antivirus software.

The droppers are designed to drop a new version of SharkBot, dubbed V2 by Dutch security firm ThreatFabric, which features an updated command-and-control (C2) communication mechanism, a domain generation algorithm (DGA), and a fully refactored codebase.

Fox-IT said it discovered a newer version 2.25 on August 22, 2022, that introduces a function to siphon cookies when victims log in to their bank accounts, while also removing the ability to automatically reply to incoming messages with links to the malware for propagation.

Samsung suffered a data breach that exposed some personal information from its U.S. customers.