In an unexpected turn of events, researchers in India have made the discovery that “quantum noise” which was always thought to be detrimental to quantum systems, is potentially beneficial in some situations. This new study could pave the way for more stable and effective quantum technologies in the future.
The research was conducted by scientists from the Raman Research Institute (RRI) in Bengaluru. Scientists from the Indian Institute of Science, IISER Kolkata and the University of Calgary have identified this breakthrough. Their work is centred on an odd phenomenon in quantum physics called entanglement. In layman terms entanglement refers to two or more particles getting “entangled” so that the state of one will influence the other, even when they are distant apart.
When noise enters a quantum system it disrupts this entanglement. This is known as decoherence and it has been one of the biggest challenges in creating quantum computers and other applications. But the RRI team discovered that one type of entanglement, known as “intraparticle entanglement” is more stable to noise. This type of entanglement occurs within one particle, not between two distinct ones.
The researchers have found that under special circumstances, noise has the ability to restore lost entanglement or even generate it where there was none. This occurred in a kind of noise called amplitude damping, which is analogous to the way energy seeps from a system. In such scenarios, noise was not only not an issue, but part of the solution.
When the same experiments were conducted on systems with two different particles entangled, the noise resulted in damage alone. There was no indication of revival or entanglement generation. This indicates that intraparticle entanglement is more robust and can be more beneficial in building quantum applications.
To better understand such effects, the scientists also created a analytical equation that aids in monitoring how entanglement evolves under various levels of disturbance. According to Animesh Sinha Roy, the lead author and post-doctoral researcher at RRI said “To analyse this behaviour, we derive an exact analytical expression for the concurrence (a key measure of entanglement) of an intraparticle entangled state subjected to an amplitude damping channel, which also admits an elegant geometric representation”.
Professor Urbasi Sinha, director of the Quantum Information and Computing Lab at RRI, explained “Our study lays down the general framework for decoherence in intraparticle entanglement. As a next step, one should extend this towards specific physical systems to make this even more realistic. We ourselves are working on an experiment using single photons and intraparticle entanglement in certain quantum technology applications such as Quantum Communication and Computing.”. She also added that these findings are not specific to a single kind of system and can be applicable to many platforms like neutrons and trapped ions.
There is a study that uses “Global Noise Model,” which treats the particle as whole, rather than other particle considering every part as individually. This technique provides a more realistic representation, since every component of a particle is generally interact in the same surroundings.
The scientists mentioned of three types of quantum noise: phase damping, which affects phease relationship in quantum interference. Second is depolarizing noise, which alters the state of the system in random directions. Last one is amplitude damping which represent loss of energy in the system. Findings also reveals that each of these noises stimulates different environmental disturbances.
Professor Dipankar Home of Bose Institute, Kolkata finds this exploration as an actual breakthrough in quantum eantanglement field. He also says that “It promises to open up uncharted avenues for user-friendly, commercially viable cutting- edge quantum technological applications in the presence of various models of noise/damping using a novel form of entanglement, viz. the entanglement between different properties of a single particle, called intraparticle entanglement.”
These findings made by India-Trento Programme for Advanced Research (ITPAR), which was funded for National Quantum Mission by Department of Science and Technology’s. It appeared in Frontiers in Quantum Science and Technology. To sum it up, what was previously considered a threat to quantum systems is now turning out promising. This surprising turn of events in quantum science demonstrates that the world of particles has more surprises for the Humans and Quantum world.
This major finding in quantum technology will supports the National Quantum Mission by enhancing secure defence networks, domestic innovation and worldwide collaborations. This advancement will help India’s Vishwaguru vision.
