Super-resolution optical microscopy based on photonic crystal materials

Theoretical model of the enhanced optical resolution and the principles of subdiffraction imaging using two-dimensional photonic and plasmon-polaritonic crystals is presented based on the properties of electromagnetic Bloch waves in periodic structures. The super-resolution is achieved due to coupling of evanescent components of the diffraction field generated by the object to the propagating Bloch modes of the photonic crystal space. The resolution enhancement is shown to occur in a general case of photonic-crystal-type materials with either positive or negative effective refractive index. Both signs of the effective refractive index have been observed in the imaging experiments with surface polaritonic crystals, in which individual virus imaging has been achieved.