All-silicon avalanche photodiode sensitive at 1.3 μm with picosecond time resolution

The first experimental demonstration that an all-silicon photodiode can be used to measure the pulse shape of laser diodes emitting at 1.3 μm is reported. In order to allow for light absorption at these wavelengths, the bandgap narrowing phenomenon in heavily doped silicon is exploited. The device operates as a single photon detector in a time-correlated photon counting setup. The quantum efficiency of the detector (though only 10^-7), together with the very low noise (≈100 dark pulses per second) enable easy measurements on standard diode lasers. The use of standard silicon processing and the room-temperature operation are definite advantages of the device