A Graphene Waveguide For Electrons

American physical Society  November 22, 2019 An electron carrying information in its quantum state and acting according to its wave nature can travel though a waveguide, but if multiple modes are available, then the electron can switch between them and lose information. An international team of researchers (USA – MIT, Japan, France) designed a device that includes a graphene flake sandwiched between two insulating sheets. On top of this structure sits a single carbon nanotube. A voltage applied across the CNT induces an electrostatic potential shaped like a rain gutter that extends down into the flake. The potential traps the […]

Thinnest optical waveguide channels light within just three layers of atoms

Science Daily  August 12, 2019 A team of researchers in the US (UC San Diego, City University of New York, Johns Hopkins University) present an experimental demonstration of light guiding in an atomically thick tungsten disulfide membrane patterned as a photonic crystal structure. In this scheme, two-dimensional tungsten disulfide excitonic photoluminescence couples into quasi-guided photonic crystal modes known as resonant-type Wood’s anomalies. These modes propagate via total internal reflection with only a small portion of the light diffracted to the far field. Such light guiding at the ultimate limit provides more possibilities to miniaturize optoelectronic devices and to test fundamental […]