Reconfigurable Surface Plasmon Resonance Photodetector with a MEMS Deformable Cantilever

Plasmonic photodetectors have many useful characteristics, such as wavelength- or polarization-specific photodetection. Although reconfigurable plasmonic structures have been intensively studied, reconfiguration of the optical characteristics of a plasmonic photodetector has not yet been reported. Here, we report a gold diffraction-grating-type plasmonic photodetector that reconfigures its optical characteristics with a MEMS deformable cantilever. By reconfiguring the photodetector characteristics using an angular scan of the cantilever over -21° to 21°, the peak shifts of the photocurrent signal waveform are found to depend on the wavelength over 1200∼1500 nm, which is consistent with SPR theory. The proposed reconfigurable plasmonic photodetector allowed us to obtain spectroscopic information on the light in a demonstration experiment.