Lights, camera, photon!

For decades, quantum imaging has promised sharper images and greater light sensitivity than classical methods by exploiting the unique properties of quantum light, such as photon entanglement. But the approaches to do so rely on delicate, specially engineered light sources that are easily overwhelmed by real-world noise, and it is difficult to generate quantum light bright enough for practical use.

Mostafavi et al. developed a quantum imaging scheme that uses advanced photon-counting sensors to extract quantum features from natural light sources and produce extraordinarily clear images.

“Our technique isolates the ‘quantum features’ hidden in ordinary light, allowing us to see what’s invisible to conventional cameras,” said author Fatemeh Mostafavi. “By carefully selecting and counting photons in the image field, we can reconstruct images with exceptional clarity, even in noisy environments where conventional imaging fails.”

The researchers used a single-pixel camera with photon-number-resolving capabilities which employs a technique known as conditional photon detection that isolates specific photon interactions to filter out unwanted noise.

In experiments, the camera revealed objects that were completely obscured by noise when classical methods were used; and it even produced imaging by detecting vacuum fluctuations, the subtle quantum ripples that exist in empty space.

“This technology could revolutionize scenarios where light is scarce or overwhelmed by noise and interference, such as in medical imaging, astronomy, and lidar,” said author Omar Magaña-Loaiza. “By bypassing traditional quantum light sources, this represents a major advance in the field of quantum imaging and promises to be more accessible, scalable, and practical for real-world applications.”

Source: “Multiphoton quantum imaging using natural light,” by Fatemeh Mostafavi, Mingyuan Hong, Riley B. Dawkins, Jannatul Ferdous, Ian Baum, Rui-Bo Jin, Roberto de J. León-Montiel, Chenglong You, and Omar S. Magaña-Loaiza, Applied Physics Reviews (2025). The article can be accessed at https://doi.org/10.1063/5.0234062 .