PRL Ahmedabad Unveils Groundbreaking Quantum Device Named Jonaki
In a significant leap for India's scientific capabilities, researchers at the Physical Research Laboratory (PRL) in Ahmedabad have engineered a revolutionary compact device that generates pairs of interconnected light particles, paving the way for absolutely secure, unbreakable communication systems. This innovative apparatus, christened Jonaki—meaning firefly in Bengali—represents the nation's first indigenously developed, ready-to-deploy quantum technology solution.
A Compact Powerhouse for Unbreakable Security
Remarkably portable, Jonaki measures roughly the size of a standard tablet and weighs a mere 1.5 kilograms. Despite its modest dimensions, it is engineered to produce entangled photon pairs, a fundamental requirement for quantum key distribution (QKD) systems that render message interception theoretically impossible. Dr. Goutam Samanta, the research leader at PRL's Photonic Sciences Laboratory, emphasized the device's mission during the Student Conference on Optics and Photonics - Optical Society of India Symposium (SCOPOSIS).
"Our objective is to democratize quantum technology, transitioning it from exclusive, high-end laboratories into the hands of Indian educational institutions. By offering an affordable, user-friendly device, PRL is equipping undergraduate colleges with the tools to cultivate the next generation of quantum scientists," Dr. Samanta explained to The Times of India.
Core Technology: The Magic of Entangled Photons
At its heart, Jonaki functions as an entangled photon source. It operates by directing a laser beam through a specialized nonlinear crystal, thereby creating pairs of photons—minute particles of light with a wavelength of 810 nanometers—that become quantum-mechanically linked. This phenomenon, known as quantum entanglement, is a cornerstone of modern physics. The particles behave as interconnected twins; any measurement or disturbance affecting one instantaneously influences its partner, regardless of distance.
This unique property is the bedrock of ultra-secure communication. "Any attempt by an eavesdropper to intercept or observe one photon irrevocably disrupts the delicate quantum state, immediately alerting the communicating parties to the security breach," Dr. Samanta detailed. This forms the basis for entanglement-based QKD, ensuring that secret keys for encrypting messages remain inviolable.
Diverse Applications: From Drones to Precision Metrology
Jonaki is specifically designed to support advanced, practical deployments beyond traditional lab settings. A primary application is in free-space quantum communication, including drone-based systems. In such a setup, Jonaki would serve as the entangled photon source. One photon from each pair could be transmitted through the air to a ground station via an optical link, while its twin is retained at another node, enabling secure key generation or quantum correlation tests over airborne channels.
Beyond secure messaging, the device promises transformative advances in precision measurement and sensing. "Entangled photons exhibit extraordinary sensitivity to minute changes in optical properties, far surpassing the capabilities of conventional classical light sources. This enables high-precision metrology and sensing applications that outperform existing optical techniques," Samanta added.
World-Class Performance and Accessibility
According to performance metrics released by PRL, Jonaki demonstrates exceptional efficacy. It generates a minimum of one million entangled photon pairs per second for every milliwatt of input power, positioning it among the top-tier devices globally. The system achieves over 98% accuracy on standard quantum benchmarking tests, including a Bell-state fidelity exceeding 98% and a strong violation of Bell inequalities—critical benchmarks for high-quality quantum communication and metrology experiments.
Notably, Jonaki overcomes common barriers to quantum technology adoption. Unlike typical quantum setups that require extensive laboratory space (often occupying entire optical tables) and continuous manual calibration, Jonaki operates stably at room temperature, is self-aligning, and features direct optical fiber connectivity, making it essentially a plug-and-play system. While comparable international systems can cost over ₹30 lakh, Jonaki is engineered to be both more advanced and significantly more accessible, particularly for academic and research purposes.
Empowering India's Quantum Future
The development of Jonaki marks a pivotal moment in India's journey toward technological self-reliance in the quantum domain. By creating an affordable, portable, and high-performance entangled photon source, PRL Ahmedabad is not only advancing the frontiers of secure communication and precision science but also actively fostering a skilled workforce. This initiative ensures that cutting-edge quantum research and education are no longer confined to elite institutions but can flourish across undergraduate colleges nationwide, empowering the next wave of Indian innovators in photonics and quantum information science.
