Surface plasmon enhanced optoelectronics

Metallic nano-structures such as nano-antennas and nano-gratings operate effectively as a coupling structure for incident beams to surface plasmon polaritons (SPPs). When deposited on a semiconductor such nano-structures ensure strong field overlap with active regions while operating simultaneously as a device electrode. The excitation of SPPs alters conventional trade-offs between responsivity and speed in photodetectors, or modulation and speed in modulators, because the active region can be shrunk to nano-scale dimensions while maintaining good optoelectronic performance due to field enhancement. Surface plasmon enhanced photodetectors and modulators on semiconductors are reviewed and discussed.