For the first time, scientists have demonstrated the ability to manipulate and identify small numbers of highly correlated interacting photons.
The research in which this has been verified has been carried out by the team led by Sahand Mahmoodian, from the University of Sydney in Australia, and Natasha Tomm, from the University of Basel in Switzerland. The Leibniz University of Hanover and the Ruhr University in Bochum, both in Germany, have also collaborated.
This unprecedented achievement represents an important milestone in the development of quantum technologies.
The stimulated emission of light, postulated by Einstein in 1916, is widely observed for large numbers of photons and laid the foundation for the invention of the laser. Thanks to the new research, stimulated emission has now been observed for single photons as well.
Specifically, the scientists were able to measure the direct time delay between a photon and a bound pair of photons scattering away from a single quantum dot.
Quantum dots are artificially created nanometer structures that in some respects behave like artificial atoms.
“This opens the door to the manipulation of what we can call ‘quantum light,'” Mahmoodian points out.
Artist’s impression of how photons bind after an interaction with an artificial atom. (Illustration: The University of Basel)
Applications of the progress achieved include advances in quantum measurement techniques and in photonic quantum computing.
The next steps in this line of research will be to find out how this new capability can be used in a way that makes it possible to generate useful light states for fault-tolerant quantum computing.
Mahmoodian and Tomm’s team discuss the technical details of their breakthrough in the academic journal Nature Physics, under the title “Photon bound state dynamics from a single artificial atom.” (Fountain: NCYT de Amazings)