Graphene optical sensor

A graphene optical sensor comprising:

• a graphene layer having a surface;
• a first electrode and a second electrode, provided directly on the surface of the graphene layer, and space apart in a first direction parallel to the surface of the graphene layer;
• and
• a plurality of plasmonic antennas provided directly on the surface of the graphene layer between the first and second electrodes,
• wherein each plasmonic antenna of the plurality of plasmonic antennas, in a plan view, includes:
• a first rod portion extending in a second direction inclined from the first direction, and
• a second rod portion extending in a third direction inclined from the first direction in a direction opposite the second direction with reference to the first direction, and intersecting the first rod portion, and wherein:
• the plurality of the plasmonic antennas is arranged periodically in the second direction and in the third direction,
• an angle formed between the first direction and the second direction is in a range greater than or equal to 40° and less than or equal to 50°, and
• an angle formed between the first direction and the third direction is in a range greater than or equal to 40° and less than or equal to 50°.