Tuning optical a‐SiC/a‐Si active filters by UV bias light in the visible and infrared spectral ranges

Abstract

Visible range to telecom band spectral translation is accomplished using an amorphous SiC pi'n/pin wavelength selector under appropriate front and back optical light bias. Results show that background intensity works as selectors in the infrared region, shifting the sensor sensitivity. Low intensities select the near‐infrared range while high intensities select the visible part according to its wavelength. Here, the optical gain is very high in the infrared/red range, decreases in the green range, stays close to one in the blue region and strongly decreases in the near‐UV range. The transfer characteristics effects due to changes in steady state light intensity and wavelength backgrounds are presented. The relationship between the optical inputs and the output signal is established. A capacitive optoelectronic model is presented and tested using the experimental results. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Light Memory Operation Based on a Double Pin SiC Device

“…This shows the controlled long-pass filtering properties of the device. Depending on the background intensity selects the infrared or the visible spectral ranges; low fluxes select the near infrared region and cuts the visible one, the reddish part of the spectrum is selected at medium fluxes, and high fluxes tune the red/green ranges [5]. Fig.…”

VIS/NIR wavelength selector based on a multilayer pi'n/pin a‐SiC:H optical filter

“…Under back irradiation the electric field decreases mainly at the i-n back interface quenching the long wavelength input signals in different ways. This effect may be due to the increased absorption under back irradiation that increases the number of carriers generated by the long wavelength photons [7]. So, by switching between front and back irradiation the photonic function is modified from a long-to a band-pass filter (Fig.…”

“…To analyze the effect of the background in the input channels magnitude, several monochromatic pulsed lights separately (850 nm, 697 nm, 626 nm, 524 nm, 470 nm, 400 nm; input channels) or combined (MUX signal) illuminated the device at 12000 bps [7]. Steady state optical bias was superimposed separately from the front and back sides and the photocurrent measured.…”