Coherent imaging of local fields in photonic crystals

Summary form only given. In the past years, much research has been focused on so called photonic crystals. Different ways of fabricating and simulating these structures have been introduced. Characterization is performed mostly with black box experiments, where reflected or transmitted light is detected. We demonstrate a different approach, which allows us to take a direct look inside such structures. With a heterodyne interferometric photon scanning tunneling microscope (PSTM), we are able to visualize not only the amplitude of the local optical field, but also the phase information of light propagating inside the crystal. Heterodyne interferometric photon scanning tunneling microscopy gives detailed insight in reflected and transmitted waves as they develop through periodic structures. Ultimately, this method will allow us to visualize the opening of a stop gap in one or two-dimensional photonic crystals.