An electrical trigger fires single, identical photons  October 8, 2020 An international team of researchers (USA – Lawrence Berkeley National Laboratory, Montana State University, Spain) has demonstrated electrically stimulated photon emission from individual atomic defects in monolayer WS2 and directly correlated the emission with the local atomic and electronic structure. Radiative transitions are locally excited by sequential inelastic electron tunneling from a metallic tip into selected discrete defect states in the WS2 bandgap. Coupling to the optical far field is mediated by tip plasmons, which transduce the excess energy into a single photon. The applied tip-sample voltage determines the transition energy. Inelastic charge carrier injection into […]

Tiny bubbles make a quantum leap

EurekAlert  July 13, 2020 An international team of researchers (USA – UC Berkeley, Columbia University, industry, Montana State University, Germany, Japan) found that placing sufficient strain in a 2D material–tungsten diselenide creates localized states that can yield single-photon emitters. The team was able to directly image these states for the first time, revealing that even at room temperature they are highly tunable and act as quantum dots, tightly confined pieces of semiconductors that emit light. Fully tunable, room-temperature single-photon emitters are now within our grasp, paving the way for controllable–and practical quantum photonic devices. These devices can be the foundation […]