title: Ultrahigh light transmission through a C-shaped nanoaperture.
abstract: Optical resolution beyond the diffraction limit can be achieved by use of a metallic nanoaperture in a near-field optical system. Conventional nanoapertures have very low power throughput. Using a numerical finite-difference time domain method, we discovered a unique C-shaped aperture that provides approximately 3 orders of magnitude more power throughput than a conventional square aperture with a similar near-field spot size of approximately 0.1 lambda. Microwave experiments at 6 GHz quantitatively confirmed the simulated transmission enhancement. The high transmission of the C-aperture--or one of the related shapes--is linked to both a propagation mode in the aperture and local surface plasmons.
authors.affiliation: Department of Electrical Engineering, Stanford University, Palo Alto, California 94305, USA.
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Shi
authors.forename: Lambertus
authors.initials: L
authors.lastname: Hesselink
authors.forename: Robert L
authors.initials: RL
authors.lastname: Thornton