New discoveries bring progress in photon calculation

International researchers led by Philip Walther from the University of Vienna have made significant breakthroughs in the field of quantum technology, successfully demonstrating quantum interference between multiple single photons using a new resource-saving platform. This work, published in Science Advances, represents a significant advancement in the field of quantum computing and paves the way for more scalable quantum technologies.

The interference between photons is a fundamental phenomenon in quantum optics and the cornerstone of optical quantum computation. It involves using the characteristics of light (such as the wave particle duality of light) to induce interference modes, thereby achieving the encoding and processing of quantum information.

In traditional multiphoton experiments, spatial encoding is commonly used, which involves manipulating photons on different spatial paths to induce interference. These experiments require complex equipment and numerous components, making them resource intensive and difficult to scale.
In contrast, an international team composed of scientists from the University of Vienna, Politecnico di Milano, and the Free University of Brussels chose a time coding based approach. This technique manipulates the temporal rather than spatial statistics of photons.

To achieve this method, they developed an innovative architecture using fiber optic loops at the Christian Doppler Laboratory at the University of Vienna. This design can reuse the same optical components to achieve efficient multiphoton interference with minimal physical resources.

Multiphoton interference network
The first author Lorenzo Carosini explained, "In our experiment, we observed quantum interference between up to eight photons, exceeding the scale of most existing experiments. Thanks to the versatility of our method, the interference mode can be reconfigured and the experimental scale can be expanded without changing the optical device."

The research results indicate that compared with traditional spatial encoding methods, the implemented architecture has significant resource efficiency, paving the way for more easily accessible and scalable quantum technologies.

Source: Physicist Organization Network