Phys.org March 28, 2023 Optical parametric oscillators are widely used to generate coherent light at frequencies not accessible by conventional laser gain. However, chip-based parametric oscillators operating in the visible spectrum have suffered from pump-to-signal conversion efficiencies typically less than 0.1%. A team of researchers in the US (NIST, University of Maryland) demonstrated efficient optical parametric oscillators based on silicon nitride photonics that address frequencies between 260 and 510 THz. Pumping silicon nitride microrings near 385 THz yielded monochromatic signal and idler waves with unprecedented output powers in this wavelength range. They estimated on-chip output powers (separately for the signal […]
Category Archives: Quantum devices
A new platform for customizable quantum devices
Phys.org February 24, 2022 A team of researchers in the US (MIT, Columbia University, University of Chicago, Northwestern University) focused on a group of molecules with a central chromium atom surrounded by four hydrocarbon molecules to demonstrate how a particular molecular family of qubits can be finely tuned over a broad spectrum. They used synthetic chemistry to modify the physics of the qubits. Using the ligand field strength, they demonstrated remarkable fine tuning and showed that the ligand field strengths are adjustable over a relatively broad spectrum, and that it also controls the molecule’s electronic properties. The light emitted by […]
Towards straintronics: Guiding excitons in 2D materials
Science Daily October 30, 2021 Strain engineering is a powerful tool in designing artificial platforms for high-temperature excitonic quantum devices. An international team of researchers (USA – City College of New York, Germany, Japan) has created excitonic wires, essentially one-dimensional channels for excitons in what is otherwise a two-dimensional semiconductor by depositing the atomically thin 2D crystal on top of a microscopically small wire they created a small, elongated dent in the two-dimensional material, slightly pulling apart the atoms in the two-dimensional crystal and inducing strain in the material. For excitons, this dent is much like a pipe and once trapped […]