Quantum sensing achieves unprecedented accuracy with optical displacement detection

A study led by the University of Portsmouth has achieved unprecedented accuracy in detecting small changes in light displacement at the nanoscale. This is related to characterization of birefringent materials and high accuracy measurements of rotation.

Quantum sensing breakthroughs are featured in Journal Physical Review A and can revolutionize many aspects of everyday life, industry and science.

Imagine two photons, a large number of light particles intertwined in a unique way. When these photons pass through a device that divides particles of light into two paths known as beam splitters, they interfere with each other in a special pattern. By analyzing these patterns, the researchers have developed a highly accurate method for detecting even the smallest initial spatial shifts between them.

Researchers have developed a technique that suggests that quantum interference detects such displacements and allows for more accuracy than traditional measurement techniques.

What is even more noteworthy about this proposed method is its ability to maintain accuracy regardless of the size of the displacement, and is extremely reliable for tracking changes over time.

“This development of quantum sensing represents an important step to making high-precision measurement tools more practical and accessible, with widespread impacts across multiple fields,” said Professor Vincenzo Tamma, lead researcher for the study and director of the Quantum Science and Technology Hub at the University of Portsmouth.

“Understanding the quantum nature of the world around us will allow us to go beyond the capabilities of classical physics and classical devices. This latest research will help our universe, particularly quantum interference and entanglement, to better utilize quantum laws for developing quantum technology.”

The study also found that even simple and inexpensive detectors known as bucket detectors can effectively estimate small displacements. This means that high-precision quantum measurements can be achieved without the need for expensive and complex instruments, making advanced sensing technologies more accessible in a variety of industries.

Professor Tamma said, “Now, many quantum sensory technologies are limited to high-end labs due to their complexity and cost.

“This research brings us closer to integration of quantum sensing into mainstream applications by developing ways to achieve ultimate quantum sensitivity with simpler and more affordable equipment.”

This study, which was included in the journal editor’s suggestion, promises to achieve essentially the highest possible accuracy in real-world scenarios.

“We have shown that this technique is feasible and efficient for real-world applications,” Professor Tamma added. “The main experimental groups have already worked with us in leading quantum sensing technology developed in the quantum technology hub to test and realise such technology.

There are quantum superpositions (the ability of particles to superimpose two states at the same time), intertwining between two particles (the ability to instantly change the state of one particle by measuring its entangled counterpart, even at large distances), and quantum interference (the waves are inhabited by scientists in the waves.

The Quantum Science and Technology Hub (QSTH) works with several partners around the world, including many academic institutions and industries such as IBM and space-based quantum technology company Xairos to achieve a deeper understanding of quantum science, develop new quantum technologies, and boost the industrial use of quantum technology at the intersections between different disciples.

QSTH connects the university’s core quantum science and technology staff with artificial intelligence (AI), biomedical engineering, medicine, computing, environmental science, gravity experts, and external collaborators from four continents.