Quantum key distribution using quantum dot single-photon emitting diodes in the red and near infrared spectral range

Abstract

We report on in-lab free space quantum key distribution (QKD) experiments over 40 cm distance using highly efficient electrically driven quantum dot single-photon sources emitting in the red as well as near-infrared spectral range. In the case of infrared emitting devices, we achieve sifted key rates of 27.2 kbit s(-1)(35.4 kbit s(-1)) at a quantum bit error rate (QBER) of 3.9% (3.8%) and a g((2))(0) value of 0.35 (0.49) at moderate (high) excitation. The red emitting diodes generate sifted keys at a rate of 95.0 kbit s(-1) at a QBER of 4.1% and a g((2))(0) value of 0.49. This first successful proof of principle QKD experiment based on electrically operated semiconductor single-photon sources can be considered as a major step toward practical and efficient quantum cryptography scenarios.