Fig. 1
From: Surface plasmon induced direct detection of long wavelength photons
Antenna-assisted subwavelength OMSM structure for millimeter and terahertz waves detection with gold and InSb as metal and semiconductor. a Schematic of the ohmic metal–semiconductor–metal (OMSM) structure in the center of the antenna-assisted OMSM structure (not drawn to scale). The wavelength of the incident photons λ is much longer than the length of the semiconductor L to meet the subwavelength requirement. s is the spacing between the edges of the two ohmic contacts. W and t are the width and thickness of the semiconductor layer, respectively. The inset is a false-colored SEM image of the fabricated device, a planar Au dipole antenna. The scale bar is 1 mm. b Zero bias case: symmetry prevents a photocurrent. c Biased case: The unidirectional movement of non-equilibrium electrons forms the photocurrent. M and S in b and c represent metal and semiconductor, respectively
