India makes breakthrough in quantum secure communication

• Encryption becomes virtually unbreakable, making it highly advantageous for critical sectors including defence, finance, telecommunications, and other strategic areas.

India’s advancement in defence and cyber security marks a significant milestone with the successful demonstration of free-space quantum secure communication using quantum entanglement.

Announced by Defence Minister Rajnath Singh, the breakthrough signifies the country’s entry into a new quantum era of secure communication, offering transformative potential for future warfare and strategic applications.

The accomplishment was achieved through collaborative efforts at the DRDO-Industry-Academia Centre of Excellence (DIA-CoE) at IIT Delhi, where researchers transmitted quantum entangled particles over a free-space optical link spanning more than one kilometre within the campus.

The experiment recorded a secure key rate of nearly 240 bits per second with a quantum bit error rate below seven per cent. Such parameters highlight the robustness and reliability of the technology for secure data transmission.

Quantum entanglement-based communication provides a security paradigm fundamentally superior to traditional encryption methods. This technique ensures that any interception attempt disturbs the quantum state of entangled photons, thereby revealing eavesdropping efforts instantly.

Consequently, the encryption becomes virtually unbreakable, making it highly advantageous for critical sectors including defence, finance, telecommunications, and other strategic areas.

Moreover, this approach obviates the need for laying conventional optical fibres, which is especially beneficial for deployment in remote or densely populated regions where establishing such infrastructure is challenging and costly.

The project titled “Design and development of photonic technologies for free space QKD” was sanctioned by the Directorate of Futuristic Technology Management (DFTM), DRDO. The demonstration was led by Professor Bhaskar Kanseri’s research group and witnessed by senior officials from DRDO and IIT Delhi.

Such institutional collaboration exemplifies the synergy between academia, industry, and defence in fostering cutting-edge technological innovation.

This achievement is a continuation of the commendable progress made by the team. In 2022, they successfully established India’s first intercity quantum communication link between Vindhyachal and Prayagraj using underground optical fibre, followed by a 100km quantum key distribution via telecom-grade fibre in 2024.

These efforts form part of DRDO’s DIA-CoEs initiative, which has established 15 Centres of Excellence across leading institutions to nurture frontier defence technologies.