Optical Probe for Nondestructive Wafer-Scale Characterization of Photonic Elements

This letter describes fabrication and operation of a microfabricated photonic waveguide loop probe for nondestructive evanescent coupling and localized testing of nanophotonic devices and circuits. A microfabricated silicon (Si) waveguide (≈300 nm × 260 nm cross section) loop forming a ≈10 μm diameter half-circle is suspended in air at the tip of a cantilever extending from a single-mode fiber-con...