Surface plasmon enhanced optoelectronics

Abstract

Metallic nanostructures can be designed to operate effectively as a coupling structure for incident beams to surface plasmon polaritons (SPPs). On a semiconductor, metal nanostructures can act simultaneously as a device electrode while ensuring strong optical field overlap with the active region. Additionally, SPP fields can be confined to sub-wavelength dimensions and significantly enhanced relative to the exciting field. These features are very attractive for nano-scale optoelectronic devices such as photodetectors as the excitation of SPPs alters conventional trade-offs between responsivity and speed respectively. This is due to the facts that sub-wavelength confinement enables the active region to be shrunk to nano-scale dimensions yet good optoelectronic performance can be maintained due to the SPP field enhancement. In this paper we discuss recent progress on surface plasmon enhanced photodetectors.