New Delhi: In a groundbreaking scientific milestone, India has successfully demonstrated quantum entanglement-based free-space quantum secure communication over a distance exceeding 1 km, placing the country firmly at the forefront of next-generation cyber defence technology.
The experiment was conducted by DRDO-Industry-Academia Centre of Excellence (DIA-CoE) at IIT Delhi as part of the DRDO project titled “Design and development of photonic technologies for free space QKD”. The communication was achieved via a free-space optical link on the IIT Delhi campus and marks a major step forward in secure quantum communication and future warfare readiness.
Key Metrics and Technological Impact
- Secure Key Rate: ~240 bits/second
- Quantum Bit Error Rate (QBER): < 7%
- Technology: Entanglement-assisted Quantum Key Distribution (QKD)
This successful demonstration validates the potential of quantum entanglement, a phenomenon where two or more particles remain interconnected regardless of the distance between them. Any attempt to intercept or measure entangled particles disturbs the system, instantly alerting users to eavesdropping attempts.
Implications for National Security and Strategic Sectors
Defence Minister Mr Rajnath Singh hailed the development as a “game changer in future warfare”, congratulating both DRDO and IIT Delhi for ushering India into a new quantum era. He emphasized the strategic potential of this technology in securing communications across defence, finance, and telecom sectors.
Quantum communication is considered unbreakable by design, unlike traditional encryption that can be compromised with advanced computing. The use of free-space QKD also circumvents the need for laying expensive and vulnerable fiber-optic cables, offering a viable solution in urban and remote terrains.
Part of DRDO’s Vision for Quantum Leadership
This experiment follows a series of successful DRDO-supported quantum technology projects-
- 2022: First intercity quantum link between Vindhyachal and Prayagraj via underground dark fiber
- 2024: Quantum key distribution over a 100 km spool of telecom-grade optical fiber
- 2025: First free-space quantum communication over 1 km using entanglement
The projects are driven under the DRDO’s 15 Centres of Excellence (DIA-CoEs) in partnership with leading institutions like IITs, IISc, and major universities, supporting cutting-edge defence R&D.
Present during the demonstration were dignitaries including the DRDO DG (MED, COS & CS), Director SAG, Director DFTM, IIT Delhi Dean (R&D), and DRDO scientists, along with Prof Bhaskar Kanseri’s team, who led the experimental effort.
Voices of Support
Dr Samir V Kamat, Secretary, Department of Defence R&D and DRDO Chairman, lauded the team for achieving “real-time secure communication powered by quantum physics.”
Prof Rangan Banerjee, Director, IIT Delhi, emphasized the significance of academia-industry-defence collaboration in pushing the boundaries of quantum research.
