High-Polarization-Discriminating Infrared Detection Using a Single Quantum Well Sandwiched in Plasmonic Micro-Cavity

Abstract

Polarimetric imaging has proved its value in medical diagnostics, bionics, remote sensing, astronomy, and in many other wide fields. Pixel-level solid monolithically integrated polarimetric imaging photo-detectors are the trend for infrared polarimetric imaging devices. For better polarimetric imaging performance the high polarization discriminating detectors are very much critical. Here we demonstrate the high infrared light polarization resolving capabilities of a quantum well (QW) detector in hybrid structure of single QW and plasmonic micro-cavity that uses QW as an active structure in the near field regime of plasmonic effect enhanced cavity, in which the photoelectric conversion in such a plasmonic micro-cavity has been realized. The detector's extinction ratio reaches 65 at the wavelength of 14.7 μm, about 6 times enhanced in such a type of pixel-level polarization long wave infrared photodetectors. The enhancement mechanism is attributed to artificial plasmonic modulation on optical propagation and distribution in the plasmonic micro-cavities.

Circular Polarization Discrimination Enhanced by Anisotropic Media

“…Vertical semiconductor nanowire arrays have been widely investigated for photodetectors, [ 37–41 ] solar cells, [ 42 ] LEDs, [ 43 ] lasers, [ 44 ] and sensors [ 45 ] owing to their unique properties, such as their anisotropic geometry, high surface‐to‐volume ratio, small footprint, crystalline perfection, and light trapping effect. [ 46,47 ] In the following, we present that the integration of a nanowire array with an asymmetric metamaterial leads to a high CPER due to the optical anisotropy of the nanowires.…”

Angular dependence of optical modes in metal-insulator-metal coupled quantum well infrared photodetector

“…These three peaks can be attributed to the third-order SPP, second-order SPP and the LSP mode resonances. 10 Due to the E z -sensitive characteristic of the QW, the average square of the electric field component along the z-direction within the QW active layer is calculated to define the optical energy …”

“…They can hardly escape from the cavity due to the lateral reflections at the two ends of the metal stripe caused by the impendence mismatch between the single-metal and double-metal areas. They go back and forth to form the Fabry-Perot-type resonance, [8][9][10] resulting in the greatly enhanced electric field localization by a factor of 7. The resonant wavelength of the LSP mode can be estimated by λ LSP = 2s n MIM /m, where n MIM is the effective refractive index of the TM mode in the MIM waveguide structure and m is the order of the Fabry-Perot mode.…”

“…9 The integration of the MIM structure and the QWIP has shown the improved photo-responsivity and the high extinguish ratio in polarization detection. 10 To date most of attentions are paid to the responsivity enhancement of the MIM-QWIP device illuminated by the normal incident light, 10 while few ones laid on how the resonant modes response to the oblique incidences. Whereas the photodetectors are being developed into focal plane array (FPA) imager that consists of two-dimensional array of photodetector pixels, different pixels at different places on the FPA receive light with different incident angles.…”

Highly Desirable Photodetectors Derived from Versatile Plasmonic Nanostructures

“…It provides us a promising approach to bridge the gap between the world of nanoscale electronics and microscale photonics. [3] Although many operating mechanisms of present plasmonic photodetectors are not very clear, versatile photodetectors have been designed and fabricated in conjunction with various metallic and graphene nanostructures such as nanoparticle, [14][15][16] grating, [17][18][19] waveguide, [20,21] antenna, [22,23] and microcavity, [24][25][26][27][28] etc. [11][12][13] Especially, experimental results demonstrate that incorporation of plasmonic nanostructures in photodetectors not only has the potential to overcome the problem of light trapping at subwavelength scale, but also could suppress photon-generated carrier recombination.…”