Congratulations to Daniel Gomez et al from CSIRO and Ion Beam Group, who recently published Waveguide-Plasmon Polariton Enhanced Photochemistry in Advanced Optical Materials. The paper looked at a key process in plasmon-enhanced photocatalysis, light absorption by metal nanostructures followed by the transfer of hot charge-carriers from metal nanostructures into photocatalytically active materials. This study focused on 1D gratings of metal wires and found strong enhancements in the rate of decomposition, exhibiting a correlation with the measured optical extinction spectra of the plasmonic nanostructures.
Congratulations to Hongzhou Zhang et al from Trinity College Dublin, Deakin University, King Saud University and Beijing Institute of Technology, who recently published Nanopatterning and Electrical Tuning of MoS Layers with a Sub-Nanometre Helium Ion Beam in Nano Letters. This work focused on helium-ion microscopy, which is not only emerging as a high-resolution tool for materials imaging, but is also capable of highly accurate nanopatterning and nanofabrication. The results demonstrated the ability of ion beams in helium-ion microscopes to be effective nanofabrication tools for two-dimensional nanomaterials such as MoS2 and oxides, and potentially also graphene, phosphorene and layered transition metal carbides.
Congratulations to Qiaoliang Bao et al from Soochow University, Hong Kong Polytechnic University, Monash University and Wuhan University, who recently published Highly responsive MoS2 photodetectors enhanced by graphene quantum dots in Scientific Reports. Molybdenum disulphide (MoS2) is an attractive material for optoelectronic and photodetection applications because of its tunable bandgap and high quantum luminescence efficiency, however issues around light absorption and gain mechanics have prevented MoS2-based photodetectors from further improvement. In this study, the researchers demonstrate a photoresponsivity of approximately 104 AW-1 and a photogain of approximately 107 electrons per photon in an n-n heterostructure photodetector that consists of a multilayer MoS2 thin film covered with a thin layer of graphene quantum dots (GQDs). The enhanced light-matter interaction results from effective charge transfer and the re-absorption of photons, leading to enhanced light absorption and the creation of electron-hole pairs.
Congratulations to Ranjith Rajasekharan et al from the University of Melbourne and Humboldt-Universitat zu Berlin, who recently published Micro-concave waveguide antenna for high photon extraction from nitrogen vacancy centers in nanodiamond in Scientific Reports. In order to make practical devices using nanodiamond, highly efficient and directional emission of single photons in well-defined modes, either collimated into free space or waveguides are essential. This is a Herculean task as the photoluminescence of the NV centers is associated with two orthogonal dipoles arranged in a plane perpendicular to the NV defect symmetry axis. In this study, the research team report on a micro-concave waveguide antenna design which can effectively direct single photons from any emitter into either free space or into waveguides in a narrow cone angle with more than 80% collection efficiency irrespective of the dipole orientation. The device also enhances the spontaneous emission rate, which further increases the number of photons available for collection. The waveguide antenna has potential applications in quantum cryptography, quantum computation, spectroscopy and metrology.
Congratulations to Mainak Majumder et al from Monash University and CSIRO, who recently published Miniaturized Supercapacitors: Focused Ion Beam Reduced Graphene Oxide Supercapacitors with Enhanced Performance Metrics in Advanced Energy Materials. In this study, focused ion beam (FIB) technology was used to directly write miniaturized planar electrode systems of reduced graphene oxide on films of graphene oxide. The results may provide avenues for large-scale fabrication of arrayed, planar, high-performance micro-supercapacitors with a small environmental footprint.