Photon scanning tunneling microscopy of tailor-made photonic structures

Abstract
Optical field distributions around individually fabricated subwavelength scatterers mapped with a photon scanning tunneling microscope are presented. The photonic structures are produced from ridge waveguides using focused-ion-beam milling. This flexible technique allows us to make single holes and slits of sizes down to 30 nm. A quantitative analysis of the observed optical pattern due to interference between incoming and reflected light yields insight about subwavelength scatterers in waveguides. We conclude that light scattering into high-loss modes of the waveguide occurs.