Ahmedabad: India demonstrated its first free-space quantum key distribution (QKD) link over a distance of 5.56 km, marking a significant step towards developing secure communication networks capable of withstanding emerging quantum-era security threats.The demonstration was carried out by QNu Labs in collaboration with the Bhaskaracharya National Institute for Space Applications and Geo-informatics (BISAG-N) and IIT-Gn. The field trial was conducted on the night of September 27–28, establishing a secure quantum communication channel between BISAG-N and IIT-Gn, said a PIB release.Using QNu Labs’ Pointing, Acquisition and Tracking (PAT) system, the trial achieved a stable Quantum Bit Error Rate (QBER) below 5 per cent and generated secure keys at a rate of 230–260 bits per second (bps).The demonstration combined two layers of quantum security, said officials. They added that the trial provides a foundation for advancing India’s capabilities in secure communication infrastructure.
