Researchers from the University of Portsmouth have recently achieved a groundbreaking discovery in quantum physics that could change the way we look at nanostructures. The team led by Dr. Vincenzo Tamma, Director of the University’s Quantum Science and Technology Hub, demonstrated the ultimate sensitivity allowed by quantum physics in measuring the time delay between two photons, paving the way for unprecedented precision in current technology.
Here are some key points to understand the breakthrough:
- The team measured the interference of two photons at a beam-splitter through frequency-resolving sampling measurements.
- They proposed the use of a two-photon interferometer and introduced a technique based on frequency-resolving sampling measurements to estimate the time delay between the two photons.
- The technique exploits the quantum interference that occurs when two single photons impinging on the two faces of a beam-splitter are indistinguishable when measured at the beam-splitter output channels.
- The best precision in the measurement of the time delay is achieved when resolving such two-photon interference with sampling measurements of the two photons in their frequencies.
- The breakthrough has significant implications for a range of applications, including more feasible imaging of nanostructures, including biological samples, and nanomaterial surfaces, as well as quantum-enhanced estimation based on frequency-resolved boson sampling in optical networks.
Dr. Tamma explained that their technique allows the use of photons of the shortest duration experimentally possible without affecting the distinguishability of the time-delayed photons at the detectors, therefore maximizing the precision of the delay estimation with a remarkable reduction in the number of required pairs of photons. This means that the technique allows for relatively fast and efficient characterization of the given sample, paving the way for applications in biology and nanoengineering.
In summary, this discovery represents a significant milestone in the field of quantum physics, offering new opportunities for imaging and measurement. With further development, the potential applications of this breakthrough could lead to even more advanced imaging techniques and the creation of new technologies that could transform many industries.
Reference: Danilo Triggiani et al, Ultimate Quantum Sensitivity in the Estimation of the Delay between two Interfering Photons through Frequency-Resolving Sampling, Physical Review Applied (2023). DOI: 10.1103/PhysRevApplied.19.044068