title: Optical magnetic field mapping using a subwavelength aperture.
abstract: Local distribution of the optical magnetic field is a critical parameter in developing materials with artificially engineered optical properties. Optical magnetic field characterization in nano-scale remains a challenge, because of the weak matter-optical magnetic field interactions. Here, we demonstrate an experimental visualization of the optical magnetic field profiles by raster scanning circular apertures in metal film or in a conical probe. Optical magnetic fields of surface plasmon polaritons and radially polarized beam are visualized by measuring the transmission through metallic apertures, in excellent agreements with theoretical predictions. Our results show that Bethe-Bouwkamp aperture can be used in visualizing optical magnetic field profiles.
authors.affiliation: Center for Subwavelength Optics and Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea.
authors.forename: Hyun Woo
authors.initials: HW
authors.lastname: Kihm
authors.forename: Jineun
authors.initials: J
authors.lastname: Kim
authors.forename: Sukmo
authors.initials: S
authors.lastname: Koo
authors.forename: Jaesung
authors.initials: J
authors.lastname: Ahn
authors.forename: Kwangjun
authors.initials: K
authors.lastname: Ahn
authors.forename: Kwanggeol
authors.initials: K
authors.lastname: Lee
authors.forename: Namkyoo
authors.initials: N
authors.lastname: Park
authors.forename: Dai-Sik
authors.initials: DS
authors.lastname: Kim