All-Silicon 1.55-μm High-Resolution Photon Counting and Timing

We investigate the performances at 1.55- $\mu{\hbox{m}}$ wavelength of silicon single photon avalanche diodes (SPADs), demonstrating their suitable applicability in laser characterizations and ultra-sensitive autocorrelation measurements. We investigate the photon detection efficiency and the two-photon absorption process of both lightly doped thick SPADs and heavily doped thin SPADs. Finally, we report the accurate pulse-shape characterization of a 1.55- $\mu{\hbox{m}}$ pulsed laser by means of a thin silicon SPAD that exploits the best intrinsic time resolution of 25 ps with wide dynamic range and low measurement time.