Technologies such as biomedical imaging and spectroscopy could be enhanced by a discovery in research that involved several institutions including the University of Glasgow.
Technologies such as biomedical imaging and spectroscopy could be enhanced by a discovery in research that involved several institutions including the University of Glasgow.
Scientists have found that two-photon processes, which have applications in the study of Alzheimer’s Disease and other nervous system disorders, can be strengthened by quantum light at far higher levels than previously thought possible.
The processes normally require high-intensity light but this can cause samples to be damaged or bleached.
It was suggested many years ago—and has since been demonstrated—that entangled photon pairs could overcome this limitation. However, it has been widely believed that this quantum enhancement only survives for very faint light, raising doubts about the usefulness of the approach.
However, the new study by researchers in Scotland and Italy saw evidence of quantum enhancement which worked at nearly ten times higher light intensity levels.
The research could pave the way for new technology which offers increased signal strengths without sacrificing quantum enhancement.
The study was carried out by researchers at Strathclyde, the University of Glasgow, Università dell’Insubria in Como, and Istituto di Fotonica e Nanotecnologie del CNR in Milan. It has been published in the journal Science Advances.
Dr Lucia Caspani, former Senior Lecturer (and now Visiting Researcher) at Strathclyde’s Institute of Photonics and lead researcher in the project, said: “We have been able to demonstrate that quantum effects can still provide an advantage well beyond the level of low intensity.
"This could significantly expand the role of quantum light in applied technologies, notably within the field of biosensing.
“Our research could lay the groundwork for the next generation of quantum-enhanced sensing approaches.”
The researchers made experimental and theoretical explorations of two-photon processes and compared the quantum physics results with those of an experiment using classical, non-quantum, light.
The theoretical and experimental results were well matched, indicating that the two-photon processes driven by quantum light are more efficient than their classical counterpart, even at higher intensities where quantum enhancement has been expected to fade.
