Phys.org June 20, 2022 A team of researchers in the US (UT Austin, Auburn University) performed an extensive study of transient optical absorption of both W- and Mo-based single-crystalline monolayer TMDs grown by a recently developed laser-assisted evaporation method. All spectral features of the monolayers as grown on fused silica substrates exhibited appreciable redshifts relating to the existence of strain due to growth conditions. These systems exhibited a dramatic slowing down of exciton dynamics with an increase in carrier densities, which strongly contrasted with the monolayers in their freestanding form as well as in comparison with more traditionally grown TMDs. […]
Tag Archives: TMDs
A novel insulating state emerges in a 2D material
Nanowerk April 23, 2022 Within the Transition-metal dichalcogenides (TMD) family, iridium ditelluride (IrTe2) is ideally suited for the systematic study of competing factors that can affect a material’s electronic properties. An international team of researchers (USA – Lawrence Berkely National Laboratory, SLAC National Accelerator Laboratory, UC Berkeley, Sandford University, South Korea, Egypt) synthesized bilayer and monolayer IrTe2 samples and characterized their atomic and electronic structures. The analysis of the material showed that monolayer IrTe2 develops a large band gap that’s an order of magnitude larger than is typical for TMD systems, transforming the material into an insulator through the removal […]
Breakthrough in quantum sensing provides new material to make qubits
Phys.org March 9, 2022 Being atomically thin and amenable to external controls, 2D materials offer a new paradigm for the realization of patterned qubit fabrication and operation at room temperature for quantum information sciences applications. An international team of researchers (USA – Temple University, Northeastern University, Taiwan) has shown that the antisite defect in 2D transition metal dichalcogenides (TMDs) can provide a controllable solid-state spin qubit system. Using high-throughput atomistic simulations, they identified several neutral antisite defects in TMDs that lie deep in the bulk band gap and host a paramagnetic triplet ground state. The analysis revealed the presence of […]
Molecular bridges power up printed electronics
Nanowerk February 25, 2021 Semiconducting transition metal dichalcogenides (TMDs) can be used to make conductive inks to manufacture printed electronic and optoelectronic devices. However, defects in their structure may hinder their performance. To boost the electrical performance of TMD based devices an international team of researchers (France, Ireland, UK) has developed ‘molecular bridges’- small molecules that interconnect the TMD flakes. The molecular bridges double up as walls, healing the chemical defects at the edges of the flakes and eliminating electrical vacancies that would otherwise promote energy loss and they provide researchers with a new tool to tailor the conductivity of […]
Liquid metals come to the rescue of semiconductors
EurekAlert October 11, 2020 In theory the two-dimensional materials can result in transistors that do not waste energy during their on/off switching. However, one of the barriers with the current technologies is that the deposited ultra-thin films are full of grain boundaries so that the charge carriers are bounced back from them and hence the resistive loss increases. An international team of researchers (Australia, UCLA) has developed a new method to eliminate grain boundaries using gallium metal in its liquid state. With its low melting point (29.8 deg C) its surface is atomically smooth when melted providing many free electrons […]