Quantum Optics
Half-Wave Plate Sandwich Around K-Mirror Achieves Polarization-Independent Wavefront Rotation
K-mirrors are standard optical components for rotating wavefronts, but inherently introduce polarization changes that degrade performance in astronomical derotation and quantum photonic applications. This work solves the long-standing open problem of achieving rotation-angle-independent polarization…
Automated Optimization Achieves >60 dB Extinction in Silicon MZI Without Pre-Calibration
Researchers demonstrate over 60 dB extinction ratio in a cascaded Mach-Zehnder interferometer (MZI) on silicon photonics, using additional MZIs as tunable beamsplitters to compensate fabrication imperfections. An automated progressive optimization algorithm enables this without pre-calibration. This…
GaN Directional Couplers Enable High-Visibility Quantum Interference in Integrated Photonics
Large cross-section GaN waveguides support integrated quantum photonic circuits via directional couplers designed with beam propagation method and fabricated by ICP etching. SEM confirms high-quality facets and precise rib gaps. At 800 nm, devices exhibit single-mode operation, tunable splitting rat…