Two-color Trapped-particle Optical Microscopy
We demonstrate a method for nonintrusive scanned near-field optical microscopy. The microscope utilizes an optical trap to position accurately a 50-100-nm-diameter lithium niobate particle. The infrared trapping beam is frequency doubled in the particle, resulting in a visible microscopic optical probe. By separation of the trapping and detection wavelengths, objects that are transparent in the in