This Deeptech Start-up From IIT Madras Arms India’s Cyber Defence with Quantum Algorithms

In 2016, as India stood at the threshold of a vast digital transformation, with nearly a billion people set to come online, a quartet comprising Sunil Gupta, Srinivas Aluri, Anil Prabhakar and Mark Mathias saw both a promise and a peril. Digital platforms were booming; e-commerce, payments through apps like Paytm, online healthcare but something critical was missing: safety  

“Everyone was talking about the digital economy,” Sunil recalls, “but no one was asking the real question: what holds this economy together?” The answer was clear to him: ‘digital trust’. And India, for all its ambition, did not have the infrastructure to support it then. 

Rather than patching gaps with legacy systems, the team chose to arm defenders with tools from the future. That vision laid the foundation for QNu Labs. From the outset, the company sought to develop quantum-secure technologies a decade ahead of their time—and bring them to market. 

The Need of the Hour 

The flare-up between India and Pakistan in May 2025, which saw targeted cyber attempts to disable India’s power, telecom and critical infrastructure, underlined the country’s growing vulnerability to digital threats. 

“Optical fibre networks, despite their speed and reliability, are surprisingly easy to tap,” says Gupta, co-founder and CEO of QNu Labs. “That makes them a serious national security risk.” 

QNu’s response is Quantum Key Distribution (QKD)—a technology grounded not in mathematics but in the principles of quantum mechanics. Unlike conventional encryption, which relies on complex algorithms such as RSA or ECC, quantum encryption exploits the laws of physics to secure communications. 

QNu Labs develops quantum-safe encryption technologies that leverage the principles of quantum mechanics to exchange encryption keys securely. These solutions are designed to work across both classical and quantum environments, offering a truly next-generation cybersecurity framework. 

“Think of it like a coin flipping in the air,” Gupta explains. “While it’s spinning, it’s both heads and tails. But if you try to touch it or observe it, it collapses into one state. That’s how quantum states behave. Any attempt to intercept or copy them immediately changes them—and alerts the system.” 

This property gives quantum encryption an edge over traditional methods, especially as quantum computers approach viability. When that moment arrives, the complex mathematical encryption systems that underpin current cybersecurity frameworks could be rendered obsolete in minutes. 

 To highlight the significance of quantum encryption in national security, he pointed to real-world examples such as China’s persistent attempts to breach critical Indian infrastructure, including power grids, and the cyberattack on Ukraine’s payment systems during the Russia-Ukraine conflict, which effectively crippled the country’s economy.  

QNu Labs has already begun deploying its solutions across military communications networks, from securing fibre-optic infrastructure to Wi-Fi environments. “Information exchanged between armed forces—such as troop movements relayed via satellite—can now be encrypted using our technologies,” says Gupta. 

The company is also expanding into drone and satellite security. “Quantum-safe encryption ensures that data collected by drones remains encrypted on the device, and all communication with ground control is secure,” he adds. 

Southern Army Commander Lt Gen Dhiraj Seth agrees. “Quantum sensing is likely to have the most immediate impact on military operations,” he says. “Next-generation sensors will transform navigation, imaging and surveillance capabilities.” 

Forged in a Vacuum 

Founded and incubated at IIT Madras in 2016, QNu Labs has raised $20 million to date—including $7 million in a Series A round led by India’s National Quantum Mission. It also secured an iDEX grant in FY2021–22 for its QKD 150km project. 

But in its early days, the company faced a near-total absence of support. “When we started, there was no ecosystem for deep tech in India—let alone for quantum technology,” says Anil Prabhakar, co-founder and technical advisor. “That made funding difficult and adoption even harder.” 

Much of their early work involved evangelising: educating investors, customers and policymakers about the quantum threat landscape and its implications. 

Today, QNu Labs employs 125 people—making it one of the largest quantum technology startups globally—and holds ten patents, with another 30 to 40 filings planned by year-end. 

The quantum threat isn’t hypothetical—it’s looming. While artificial intelligence is already expanding the toolkit available to cybercriminals, quantum computing threatens to upend encryption altogether. 

“AI is still reactive,” Gupta says. “It detects and responds to threats that already exist. But it can’t prevent what hasn’t happened yet.” 

Only quantum-secure encryption, he argues, will withstand the onslaught of quantum computing. “While the world is busy solving today’s cybersecurity problems,” says Prabhakar, “we’re preparing for the tsunami that’s coming. And when it hits, AI won’t be enough. Only quantum encryption will protect critical systems.” 

QNu Labs is also forming strategic partnerships to maximise deployment. It is currently working with CDAC, Bharat Electronics Limited (BEL), ISRO and other government institutions to scale its technology. 

As warfare moves beyond trenches and tanks and into the realm of code and connectivity, cyber defence becomes not just a priority—but a necessity. In this emerging battlefield, quantum-safe encryption technologies like those developed by QNu Labs may well determine how secure a digital India truly is.