Scientists working under India’s National Quantum Mission have discovered a method to extend the lifespan of quantum entanglement by applying a precisely-timed operation to quantum systems. The Ministry of Science and Technology announced the finding, which could benefit the design and performance of future quantum computers without requiring any changes to hardware itself.
The Discovery
Entanglement occurs when two particles become linked in such a way that the state of one directly influences the state of the other, regardless of distance. However, this delicate connection weakens when particles interact with their surroundings, and can sometimes disappear entirely before the particles themselves have fully decayed — a phenomenon called entanglement sudden death.
A team from the Raman Research Institute (an autonomous body of the Department of Science and Technology), University of Calgary and Louisiana State University found that by applying a swap operation at the right moment during the decay process, they could delay or even prevent this sudden death altogether. The timing of when this operation is applied proves as crucial as the operation itself.
The researchers demonstrated their findings using polarized light particles in a controlled optical setup. By manipulating the polarization states of photons and applying a flip operation at strategic points during their natural decay, they showed that entanglement loss could be controlled. The research was published in Physical Review A in July.
The study revealed an unexpected result: the experimental behaviour did not match either of two standard textbook models for how quantum systems lose information. Instead, the findings occupied the middle ground between these two frameworks, suggesting a single unified approach that could represent multiple noise conditions depending on how parameters are adjusted.
What this means for you
For those interested in quantum computing, this work suggests that quantum processors could maintain their fragile quantum information longer simply by timing interventions correctly, rather than requiring expensive hardware redesigns. This could make quantum computers more practical and reliable as they scale up.