India has reached a significant milestone in the realm of quantum technology, as the Defence Research and Development Organisation (DRDO) in collaboration with IIT Delhi successfully demonstrated quantum entanglement-based free-space quantum secure communication over a distance of more than one kilometre. This landmark achievement, conducted through the DRDO-Industry-Academia Centre of Excellence (DIA-CoE) at IIT Delhi, places India at the cutting edge of secure communication technologies, vital for future warfare and strategic applications.
The experiment utilized a free-space optical link located on the IIT Delhi campus, achieving a secure key rate of approximately 240 bits per second, with an impressive quantum bit error rate of under 7%. This accomplishment is part of a larger initiative titled “Design and development of photonic technologies for free space QKD,” which has been sanctioned by the Directorate of Futuristic Technology Management (DFTM) of DRDO.
The demonstration was spearheaded by Professor Bhaskar Kanseri’s research team and was attended by prominent officials. Key attendees included the Director General of DRDO for Medical, Combat, and Cyber-security, alongside Directors of the SAG and DFTM, the Dean of Research and Development of IIT Delhi, the DIA-CoE Director, and several DRDO scientists. The entanglement-assisted approach applied in this experiment offers superior security compared to traditional methods. Notably, any attempt at interception disrupts the quantum state, which can then be detected by the communication system.
The implications of quantum communication are profound, promising transformative advancements across various sectors, including defence, banking, and telecommunications. Free-space Quantum Key Distribution (QKD) is especially advantageous as it does not rely on fiber-optic infrastructure, enabling secure communication even in challenging terrains and densely populated urban environments.
India has previously made significant strides in quantum communication, exemplified by an intercity quantum link established between Vindhyachal and Prayagraj in 2022, utilizing underground dark optical fiber. This was followed by a groundbreaking 100-kilometre quantum key distribution experiment via optical fiber in 2024. These continuous advancements accentuate the rapid progress being achieved under DRDO’s initiative comprising 15 Centres of Excellence established across leading academic institutions for groundbreaking defence research.
Raksha Mantri Rajnath Singh lauded the collaborative efforts of DRDO and IIT Delhi, describing this achievement as a game-changer for future warfare and national cybersecurity. Dr. Samir V. Kamat, Secretary of the Department of Defence R&D and Chairman of DRDO, along with IIT Delhi Director Prof. Rangan Banerjee, expressed their gratitude to the research team for furthering the boundaries of quantum communication technology.
