The Precision and Quantum Measurement Laboratory (PQM lab) at Inter University Centre for Astronomy and Astrophysics is developing a state-of-the-art facility dedicated to explore the fundamentals of science using very accurate optical atomic clocks. “Once the clock is ready, it will be able to detect incredibly tiny changes in energy, which can reveal things like changes in fundamental physical constants (if any), change of gravity over a tiny height, possible gravitational waves and others,” Prof Subhadeep De, Principal Investigator, PQM lab, said. For the purpose, the lab is creating high-precision instruments using quantum science for extremely accurate measurements. The lab’s research interests involve developing quantum phenomena-based technologies for metrology-grade measurements and accurate sensing. “The heart of the experimental setup is a trapped ytterbium-ion-based quantum clock,” Prof De said. The clock works by using a rare atomic process that happens at a light wavelength of 467 nanometers. To power the clock the lab is building an ultra-stable laser with an extremely narrow frequency line width, the scientist explained. Prof De also noted that the optical fiber-based distributed acoustic sensing (OF-DAS) technology in the last decade has emerged as a powerful tool for a wide range of applications. It could be early warnings of natural calamity by continuous monitoring of the seismic noise and differentiating any abnormality originating from earthquake, tsunami, volcanic eruption, structural health monitoring of cracks build-up in flyovers, bridges, railway tracks, and disaster control by timely detection of cracks. At the PQM lab, a new method for sensing vibrations using optical fibre has also been developed. It uses a very stable laser at 1,550 nm to detect and locate acoustic or seismic signals more accurately. The system tracks tiny changes in the laser’s frequency to find where and when vibrations happen, and how strong they are. The team is now working to make the system transportable with its potential application in Laser Interferometer Gravitational Wave (LIGO-India) LIGO-India event to commemorate International Year of Quantum 2025 Laser Interferometer Gravitational Wave (LIGO) detectors are among the most precise instruments in the world and quantum technologies are key to improving their sensitivity. LIGO-India, an ongoing mega science project dedicated to detect gravitational waves, is actively exploring pathways to enable quantum science and technology in improving the performance of its detector. Innovative solutions such as quantum squeezing and quantum sensors have been developed to detect the elusive gravitational waves. On Tuesday, an event was organised by LIGO-India Education and Public Outreach (LI-EPO) to showcase the current developments in quantum physics particularly to highlight its applications in gravitational wave science. Experts from various domains in quantum sciences and technologies in India came together to discuss the future of measurements, communications, and gravitational waves at IUCAA in Pune. Prof R Srianand, Director of IUCAA, inaugurated the event. “As we push the frontiers of gravitational -wave astronomy, the LIGO detectors have now entered the quantum regime, marking a major forward in precision measurement,” Dr Manasadevi P T, scientist at IUCAA, said. “This progress not only enhances our sensitivity to probe the universe using gravitational waves but also contributes meaningfully to the field of quantum sensing and metrology,” she said. Prof Debarati Chatterjee, chair of LIGO-INDIA Education and Public Outreach at IUCAA, said the day-long event was specifically held as 2025 worldwide is being celebrated as the International Year of Quantum Science and Technology. “It marks 100 years since the foundational developments in quantum mechanics and honours the groundbreaking work of scientists like Heisenberg, Schrödinger, Bohr, Einstein, and Bose, whose contributions shaped our understanding of the quantum world,” Prof Chatterjee said.
