Generation of weak coherent pulses for quantum cryptography systems

Abstract EN

This work is a trial to ensure the absolute security in any quantum cryptography (QC) protocol via building an effective hardware for satisfying the single-photon must requirement by controlling the value of mean photon number.

This was approximately achieved by building a driving circuit that provide very short pulses (≈ 10 ns) for laser diode -LD- with output power of (0.7-0.99mW) using the available electronic components in local markets.

These short pulses enable getting faint laser pulses that were further attenuated to reach mean photon number equal to 0.08 or less.