Blog
- 21/08/2019 Nanoscale Graphene Sheets Folded Into Atomic Crêpes Atom-thick sheets stacked with precise twist angle and tubular edge could be made into quantum nanomachines
- 19/08/2019 Ferromagnetism Appears In Twisted Bilayer Graphene Researchers have found that electrons organize themselves into a new kind of ferromagnet in twisted bilayer graphene (TBG).
- 16/08/2019 Atomic Force Microscopy Goes 3D Ten years ago, researchers succeeded in significantly increasing the lateral resolution of low temperature atomic force microscopy (AFM) by functionalizing the AFM tip with a single carbon monoxide (CO) molecule.
- 14/08/2019 Granular Aluminium Superinductors Could Enhance Qubit Performance Use of superconducting circuits in quantum computing architectures is growing, yet the greatest resistance they face might come from not having enough of it.
- 14/08/2019 Terahertz Light Pulses Speed Up Spin Switching A new technique to rapidly reverse a magnet’s polarity in a way that all of its spins coherently rotate could be used to develop more energy-efficient data storage devices and superfast computers in the future.
- 13/08/2019 CuInSe2 Quantum Dots Grown By Molecular Beam Epitaxy On Amorphous SiO2 surfaces The currently most efficient polycrystalline solar cells are based on the Cu(In,Ga)Se2 compound as a light absorption layer. However, in view of new concepts of nanostructured solar cells, CuInSe2 nanostructures are of high interest. In this work, we report CuInSe2 nanodots grown through a vacuum-compatible co-evaporation growth process on an amorphous surface. The density, mean size, and peak optical emission energy of the nanodots can be controlled by changing the growth temperature. Scanning transmission electron microscopy measurements confirmed the crystallinity of the nanodots as well as chemical composition and structure compatible with tetragonal CuInSe2. Photoluminescence measurements of CdS-passivated nanodots showed that the nanodots are optoelectronically active with a broad emission extending to energies above the CuInSe2 bulk bandgap and in agreement with the distribution of sizes. A blue-shift of the luminescence is observed as the average size of the nanodots gets smaller, evidencing quantum confinement in all samples. By using simple quantum confinement calculations, we correlate the photoluminescence peak emission energy with the average size of the nanodots
- 12/08/2019 This One 'Anomaly' Is Driving Physicists To Search For Light Dark Matter We buy our own products and put them under the same testing methodology so that you can easily compare them.
- 12/08/2019 Synthesizing Single-Crystalline Hexagonal Graphene Quantum Dots The Korea Advanced Institute of Science and Technology (KAIST).
- 11/08/2019 Large-grain MBE-grown GaSe on GaAs With A Mexican Hat-Like Valence Band Dispersion Atomically thin GaSe has been predicted to have a non-parabolic, Mexican hat-like valence band structure due to the shift of the valence band maximum (VBM) near the Γ point which is expected to give rise to novel, unique properties such as tunable magnetism, high effective mass suppressing direct tunneling in scaled transistors, and an improved thermoelectric figure of merit. However, the synthesis of atomically thin GaSe remains challenging. Here, we report on the growth of atomically thin GaSe by molecular beam epitaxy (MBE) and demonstrate the high quality of the resulting van der Waals epitaxial films. The full valence band structure of nominal bilayer GaSe is revealed by photoemission electron momentum microscopy (k-PEEM), confirming the presence of a distorted valence band near the Γ point. Our results open the way to demonstrating interesting new physical phenomena based on MBE-grown GaSe films and atomically thin monochalcogenides in general.
- 10/08/2019 Researchers Build Quantum Vibration Sensor That Can Measure The Smallest Units Of Sound A system that can distinguish phonons, the smallest units of sound, marks an important milestone in the development of more advanced quantum computers.