• home
• current students
• graduate
• events

Presenter: Yuanjie Pang
Supervisor: Dr. Reuven Gordon

Date: Thu, April 5, 2012
Time: 14:00:00 - 00:00:00
Place: EOW 430

ABSTRACT

ABSTRACT:

This talk presents subwavelength optics with focus on the theory and applications of subwavelength apertures in a metal film. Two main issues regarding the optics with subwavelength apertures will be discussed. The first issue regards to extraordinary optical transmission (EOT) through subwavelength apertures. We first discovered an EOT phenomenon with a total transmission through a single aperture in a perfect metal waveguide, without relying on arrays and corrugations. This concept is extended into the optical regime for boosting the throughput of an apertured near-field scanning optical microscope (NSOM) probe. The EOT NSOM probe has an enhanced optical throughput, a higher damage threshold and a single molecule scanning resolution. As the second issue, subwavelength apertures are found useful for optical trapping. Conventional optical traps such as a single beam optical tweezers are limited for trapping dielectric particles with sizes greater than 100 nm. It will be shown that using a subwavelength aperture, a stronger optical force for trapping can be induced because even a small particle can greatly change the light transmission through the aperture. Using a double-nanohole with two sharp tips, we have trapped 12 nm silica spheres (smallest dielectric particle trapped). We have also trapped and unfolded a single protein. The protential of using the trapping setup as a sensor for single protein binding will also be discussed.