Saddle-shape whispering gallery mode resonators: µm- to cm- scale

Optical Whispering Gallery Mode (WGM) of various sizes and axisymmetry-shapes have been studied and used for a variety of optical sensors. Recently, we suggested a new type of WGM resonators with a saddle shape. These structures consist of two resonators with a bridging region resembling a valley. The unique shape of the saddle-shape resonators may allow the coupling of light into the resonator using a tapered fiber, by placing the tapered fiber at the structural minima point of the valley region. This coupling configuration provides high mechanical stability while maintaining the quality (Q) factor of the joint structured resonator. Here we present saddle shape resonators of various shapes and sizes, suitable for a variety of sensing applications.