Full-Color-Adjustable Nanophotonic Device Adopting Electrochromic Poly(3,4-ethylenedioxythiophene) Thin Films.

Intercalation-based organic polymers that shift their colors during ion insertion and extraction provide a significant basis for existing electrochromic technology. Nevertheless, the complexity of modifying the structure in the skeleton or combining several diverse polymers to produce a full-color range has restricted the practical applications of electrochromic materials. Herein, we demonstrate two configurations of the poly(3,4-ethylenedioxythiophene) (PEDOT) Fabry-Perot (F-P) nanocavity-type electrochromic devices fabricated by spray coating lossless PEDOT on the F-P metasurfaces (Cr/ITO/Ag/Cr), which allows full-color response by simply controlling the thickness of dielectric layer indium tin oxide (ITO).

Breakdown flash at telecom wavelengths in InGaAs avalanche photodiodes.

Quantum key distribution (QKD) at telecom wavelengths (1260 - 1625 nm) has the potential for fast deployment due to existing optical fibre infrastructure and mature telecom technologies. At these wavelengths, Indium Gallium Arsenide (InGaAs) avalanche photodiode (APD) based detectors are the preferred choice for photon detection. Similar to their Silicon counterparts used at shorter wavelengths, they exhibit fluorescence from recombination of electron-hole pairs generated in the avalanche breakdown process.