IIT Guwahati scientists gain international recognition for their work on Quantum Entanglement

A research team at IIT Guwahati, led by a professor of physics, has studied the workings of quantum entanglement — a phenomenon that continues to baffle the finest scientific minds of the world.

The team’s theoretical research on cavity optomechanical systems has potential applications in quantum information science and can contribute towards understanding the boundary between classical and quantum physics. 

Amarendra Kumar Sarma and his research scholars Subhadeep Chakraborty and Sampreet Kalila have recently summarised their understanding in an invited review article in AVS Quantum Science, a research journal published by American Institute of Physics. The article is published as a featured article of the journal this month.

Sarma was invited to write a review article for the journal in recognition of his seminal works in quantum optics.

“Nobody knows how or why quantum entanglement happens,” Sarma said about the phenomenon that baffled even the great intellect of Einstein.  “That, however, does not make it unreal. Numerous experiments have established that entanglement is indeed a real phenomenon in subatomic systems. In fact, quantum entanglement is the building block of the second generation of quantum technology such as quantum computation, quantum cryptography, quantum teleportation, and quantum dense coding.”

Various research groups around the world are working towards understanding quantum entanglement. Sarma’s team works on understanding it in the realm of cavity optomechanics, the interaction between light and mechanical objects at low-energy scales.

“In simplified terms, a cavity optomechanical system refers to a set of mirrors where one of the mirrors is fixed while the other one is slightly movable,” Sarma said. Surprisingly, this simple model can explain the physics of a plethora of complicated optomechanical systems. Such systems provide a universal tool to achieve quantum control of mechanical motion. But beyond application, the research helps to understand the boundary between classical and quantum physics.

“We have come up with various practical schemes to enhance quantum correlations in optomechanical systems. Apart from entanglement, we are looking into the aspects of qubit transfer, photon and phonon blockade also in such systems owing to their tremendous applications in quantum communication and information sciences,” Sarma said.

More recently, the group has addressed the issue of “entanglement sudden death” under the influence of a local noisy environment, a stumbling block encountered by scientists a decade ago. The researchers have proposed a scheme to tackle such shortcomings using an optomechanical platform.