Researchers from the CNST and ITL have achieved a breakthrough in quantum photonics by simultaneously changing the color and shape of a single photon. This work, published in Physical Review Letters, represents an important step towards implementing secure quantum communication over long distances.
The team used a specially designed optical fiber probe to extract a single photon from a quantum dot, which was engineered to emit photons one at a time. The photon was then combined with a much stronger pulsed laser beam inside a nonlinear optical crystal, allowing the two light beams to interact efficiently. After exiting the crystal, the wavelength of the photon was shifted by almost 600 nm, an amount greater than the size of the entire visible spectrum. The temporal shape of the pulsed laser was also imprinted on the single photon during the color-conversion process.
This approach may enable researchers to link previously incompatible quantum technologies in a large-scale network for quantum information processing applications. The ability to simultaneously change the color and shape of a single photon could have significant implications for secure quantum communication and other quantum technologies.
Keywords: photon, quantum, communication, network, single
