Magneto-optical Faraday imaging with an apertureless scanning near field optical microscope

We have developed an apertureless Scanning Wear field Optical Microscope (S NOM) in transmission, devoted to near field magneto-optics. Our apertureles s SNOM combines an inverted optical microscope, which has been adapted to F araday effect imaging, with a commercial stand-alone Scanning Probe Microsc ope, used in Atomic Force Microscope (AFM) mode. Two different probes are v alidated as apertureless SNOM tips: a home-made etched tungsten wire and a commercial AFM silicon probe. We present and analyze preliminary images of the domain structure in iron garnets. They indicate a SNOM resolution clear ly in the sub-micrometric range. Besides, the near field magneto-optical im age presents some unexpected features, not revealed in far field images.