It’s been a busy few months in the quantum labs of India’s Defense Research & Development Organization (DRDO). The agency has reported significant advances in quantum cryptography and quantum communication, according to their news unit.
Quantum Random Number Generation
The agency reports in a news release that the DRDO Young Scientist Laboratory for Quantum Technologies (DYSL-QT) has developed a Quantum Random Number Generator (QRNG) which detects random quantum events and converts those into a stream of binary digits.
With this development India enters the club of countries who have the technology to achieve the use of quantum technology to generate random numbers. This is important because, according to the agency, random numbers have essential roles in many fields, such as quantum communication, cryptography (key generation, key wrapping, authentication etc.), scientific simulations, lotteries and fundamental physics experiments. The generation of genuine randomness is generally considered impossible with classical means. Quantum mechanics has the inherent potential of providing true random numbers and thus has become the preferred option for the scientific applications requiring randomness.
The laboratory has developed a fiber-optic branch path based QRNG. Branch path-based QRNG relies on the principle that if a single photon is incident on a balanced beam splitter, it will take either of the beam-splitter output paths randomly. As the path chosen by photon is random, the randomness is translated to sequence of bits.
QRNG system developed by the laboratory has been evaluated and verified using several tests, such as DRDO’s indigenously developed Randomness Testing Statistical Test Suite of SAG.
Quantum Communication between two DRDO Laboratories
In another advance, DRDO demonstrated secure communication using Quantum Key Distribution (QKD) technology between two DRDO labs in Hyderabad, according to information from the agency.
The team of researchers added that secure communications are vital for defense and strategic agencies world over and distribution of encryption keys from time to time is an important requirement in this context. Sharing of keys over the air or wired links requires encryption, which in turn requires encryption keys to be pre-shared. Quantum based communication offers a robust solution to sharing the keys securely.
The technology is developed by CAIR, Bengaluru and DYSL-QT, Mumbai. Quantum Communication using time-bin Quantum Key Distribution (QKD) scheme was performed under realistic conditions, according to the release. The setup also demonstrated the validation of detection of a third party trying to gain knowledge of the communication. Quantum based security against eavesdropping was validated for the deployed system at over 12kms range and 10dB attenuation over fibre optic channel.
Continuous wave laser source was used to generate photons without depolarization effect. The timing accuracy employed in the setup was of the order of picoseconds. The Single photon avalanche detector (SPAD) recorded arrival of photons and key rate was achieved in the range of kbps with low Quantum bit error rate. Software was developed for data acquisition, time synchronization, post-processing, determining Quantum bit error rate and extracting other important parameters.
The work being done at DRDO will be used to enable start-ups and SMEs in the domain of Quantum information technologies. It will also serve to define standards and crypto policies that can leverage QKD system in a unified Cipher Policy Committee (CPC) framework for more secure and pragmatic key management for current and future military cryptographic systems.