Scientists from Raman Research Institute (RRI), University of Calgary, and Louisiana State University have developed a method to preserve quantum entanglement for extended periods using a precisely timed flip operation. The research, partially funded by the Department of Science and Technology's National Quantum Mission, demonstrates that the timing of operations is as important as the operation itself in quantum systems.
The team used an optical setup with light polarization states representing excited (vertical polarization) and ground (horizontal polarization) states. By applying a well-timed operation that swapped populations between ground and excited states using a waveplate, they could control the decay process. The timing of this single flip operation determined whether entanglement sudden death could be avoided, delayed, or hastened.
Experimental results surprised researchers as they did not fit either of the two standard textbook models of quantum information loss. After nearly a year of theoretical exploration, scientists realized the experiment represented a 'tuning parameter' that connects these two frameworks, allowing a single setup to represent both noise models and all variants in between. The findings were published in the American Physical Society's Physical Review A in July 2026.
This discovery could help extend the survival time of quantum information in future quantum computers without requiring hardware modifications, addressing a fundamental limitation in quantum computing where quantum information decays over time due to environmental noise.