Nanowerk June 17, 2022 Conventionally, high-Q resonators that have a minimum loss in optical power are used to generate ultra-narrow optical features in solid-state, but they require complex and costly fabrication processes, which limits their large-scale commercial production. Researchers in Canada have demonstrated a resonator-free approach to generate such ultra-narrow features exploiting gain-enhanced polarization pulling in a twisted birefringent medium where polarization eigenmodes are frequency-dependent. Using Brillouin gain in a commercial spun fibre, they experimentally achieved a 0.72 MHz spectral dip. Further optimization can potentially reduce the linewidth to <0.1 MHz. According to the researchers their approach is simple and broadly […]
Category Archives: Optical engineering
Transforming materials with light
Nanowerk December 8, 2021 Although there are strategies to drastically alter electronic and magnetic properties by optically inducing non-trivial band topologies, emergent spin interactions and superconductivity, methods of coherently engineering optical properties on demand are far less understood. An international team of researchers (Caltech, UC Santa Barbara, South Korea) has demonstrated coherent control and giant modulation of optical nonlinearity in a van der Waals layered magnetic insulator, manganese phosphorus trisulfide (MnPS3). They observed a coherent on–off switching of its optical second harmonic generation efficiency on the timescale of 100 femtoseconds with no measurable dissipation. At driving electric fields of the order […]