Researchers at RRI Demo Free Space QKD 50 Meters Apart–But Only During the Night

(DaijiWorld) A research team headed by Urbasi Sinha at the Raman Research Institute (RRI) successfully demonstrated free space quantum distribution key between two buildings in the institute using an atmospheric channel.
This is the first time the technique – called entanglement-based quantum-key distribution – has been demonstrated using ground stations based in RRI at a distance of 50 meters apart.
“This is the country’s first free space quantum key distribution experiment. This experiment can be done and demonstrated only during the night,” Sinha told reporters who heads the Quantum Information and Computing (QuIC) laboratory at the RRI as well as India’s first project on satellite based secure quantum communications. She recently demonstrated this new protocol after sunset–invisible to anyone but to two special telescopes that are set up in RRI premises at around 50 meters apart.
This project is a joint collaboration between the RRI and India Space Research Organisation (ISRO) and both came up together in 2017 to set up a laboratory called – Quantum Experiments Using Satellite Technology (QuEST) and Sinha heads this lab.
She described that this is a breakthrough milestone in the country as this will pave the way for longer distances using atmospheric channels, which ultimately culminating with ground to satellite based secure quantum communications.