InGaAs/InP Single photon detector in the near infrared using an InGaAs/InP avalanche photodiode operated with a bipolar rectangular gating signal.

摘要

The present invention relates to a single photon detector (SPD) at an electrical communication wavelength of 1.55 μm based on an InGaAs / InP avalanche photodiode (APD). In order to operate the SPD with low backward pulse noise, a DC bias voltage lower than the breakdown voltage is applied to the InGaAs / InP APD. A bipolar spherical gating signal is superimposed on the DC bias voltage and applied to the APD to exceed the breakdown voltage for the gate on time of each period of the gate signal. The use of a bipolar spherical gating signal allows the APD to operate much lower than the breakdown voltage during gate off time, thereby making the discharge of the trapped charge carriers faster and reducing the backward pulse noise. As a result, it is possible to increase the repetition rate of the SPD.