Uncooled Zero-Bias Graphene Mid-Infrared Detectors

Uncooled mid-infrared (mid-IR) detectors with high sensitivity, zero power consumption, fast response, simple CMOS-compatible fabrication processes, small footprint, wavelength and polarization selectivity are highly desired for the nascent sensors array but so far remain elusive. This paper shows that all the above challenges can be addressed in a metasurface-mediated graphene mid-IR detector. The core of our approach is to design non-centrosymmetric metallic nanoantennas that break the symmetry of local electromagnetic field and induce directional flow of hot carriers in graphene. Our zero-bias uncooled device requires no thermal isolation and possesses a footprint of 42 μm
²
, a responsivity of 25.4 V/W at 4 μm wavelength, a noise equivalent power of 0.3 nW/Hz
^1/2
, and a setup-limited response time <; 0.1 ms.