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 applicable, offering on-demand tunability and high sensitivity, with a wide range of applications such as microwave photonic filters, slow and fast light, and optical sensing…read more. TECHNICAL ARTICLE
Graphic illustrating the fixed and rotating frames of reference of an SBF. Credit: Nature Photonics (2022)Â