APERTURELESS NEAR-FIELD OPTICAL MICROSCOPE

We demonstrate a new method whereby near-field optical microscope reso lution can be extended to the nanometer regime. The technique is based on measuring the modulation of the scattered electric field from the end of a sharp silicon tip as it is stabilized and scanned in close pr oximity to a sample surface. Our initial results demonstrate resolutio n in the 3 nm range-comparable to what can be achieved with typical at tractive mode atomic force microscopes. Theoretical considerations pre dict that the ultimate resolution achievable with this approach could be close to the atomic level.