Indian Scientists Make Major Breakthrough In Quantum Cryptography

In a major breakthrough, a team of Indian scientists has created a user-friendly way to generate unpredictable random numbers crucial for stronger quantum data encryption and provide robust cybersecurity, the Ministry of Science & Technology has said.

Quantum cryptography, also known as quantum encryption, refers to various cybersecurity methods for encrypting and transmitting secure data based on the naturally occurring and immutable laws of quantum mechanics.

The Raman Research Institute, Bengaluru, which is an autonomous institute of the Department of Science and Technology (DST), performed a photonic experiment to demonstrate a violation of what is called the Leggett Garg Inequalities (LGI) -- a litmus test for "quantumness" in a system in a loophole-free manner.

The team carried out extensive research in collaboration with researchers from the Indian Institute of Science (IISc), Bengaluru, IISER-Thiruvananthapuram and the Bose Institute, Kolkata to use such LGI violation in a completely unexplored domain -- truly unpredictable random number generation, secure against device tampering and imperfections.

These numbers are crucial in applications like cryptographic key generation, secure password creation and digital signatures, among others.

With further engineering interventions and innovations, devices adopting this method could find powerful applications not only in cybersecurity and data encryption but also in diverse areas like economic surveys and drug designing/testing.

"We have successfully generated random numbers using temporal correlations certified by the violation of the Leggett Garg Inequality (LGI)," said Professor Urbasi Sinha, faculty at the QuIC lab at Raman Research Institute, and the corresponding author of the paper published in the Physical Review Letters.

"Our experimental setup ensures a loophole-free violation of LGI, providing an additional advantage of generating loophole-free randomness," Professor Sinha added.

According to the researchers, this new method offers the enhanced protection "we all need in our daily lives, by using truly random numbers to generate keys that will be used to encrypt the passwords".

There are several advantages to generating certified random numbers using this method.

"These include the creation of strongly protected passwords, enhanced account security by resisting brute-force attacks, ensuring uniqueness, integrity thereby preventing forgery and token generation with multi-factor authentication, adding a crucial security layer in this vulnerable cyber world," explained Dr Debashis Saha, IISER Thiruvananthapuram faculty and co-author of the study.

The experiment generated over 9,00,000 random bits at a rapid rate of nearly 4,000 bits/second.