Plasmonic lens enhanced photodetectors
We demonstrate monolithic integrated quantum cascade detectors (QCDs) enhanced by plasmonic lenses.
Surface normal incident mid-infrared radiation is coupled to surface plasmon polaritons (SPP) guided to and
detected by the active region of the detector. The lens extends the optical e
ective active area of the device
up to a 5 times larger area than for standard mesa detectors or pixel devices while the electrical active region
stays the same. The extended optical area increases the absorption eciency of the presented device as well
as the room temperature performance while it o
ers a exible platform for various detector geometries. A
photocurrent response increase at room temperature up to a factor of 6 was observed.
Scanning electron microscope image of a plasmonic lens quantum cascade detector with circular gold SPP guiding region.