Abstract

In our novel experimental setup an active nanoparticle is attached to the end of a fiber tip. In order to achieve coupling, the tapered fiber tip is placed close to the surface of a microsphere resonator using the shear-force mechanism. In this way light emitted from the nanoparticle couples to the cavity, when the particle is optically pumped via the fiber. In a first experiment¹ a stabilized diode laser was frequency-tuned across a single whispering-gallery mode. The light scattered into a bare fiber tip was recorded while scanning 10 µm perpendicular to the equator of the sphere with a constant tip-sphere separation of approx. 10 nm (see cartoon in Fig. la). Figure la shows the intensity pattern versus frequency and scan distance of a two-lobed mode.

© 2001 Optical Society of America