UK researchers use “spooky” quantum mechanics to create low-light photos

Whilst conventional digital cameras sample around 100,000 photons per pixel to make an image, a team from Glasgow University has harnessed the strange power of quantum mechanics to create a digital image using fewer than one photon per pixel.

Researchers from the University’s Optics Group used a technique known as quantum ghost imaging to create an image of a wasp wing using just 50,000 particles of light.

The process  – which is described in a paper published in Nature Communications – works using quantum ghost imaging, which harnesses what Einstein called the ‘spooky action at a distance’ property of quantum entanglement, where photons are paired so that any measurement of one instantaneously gives knowledge of the state of the other, no matter the space between them.

The project – which was supported by EPSRC funding – is the latest in a series of quantum imaging breakthroughs at Glasgow University, which was recently announced by the UK government as the lead in a £29m Quantum Imaging Hub.

Developed in collaboration with researchers in Ottawa, Canada the system works by sending ultraviolet light from a laser to a non-linear crystal similar to a piece of quartz. The crystal splits every incident ultraviolet photon into two infrared photons, which exit the crystal on separate trajectories in a state of quantum entanglement.

Peter Morris, a graduate student working on the project, explained that whilst one photon illuminates the wasp wing the other photon goes to the camera sensor. Because the photons are entangled and share information between them on a quantum level, the image is formed on the camera’s sensor by photons which have never actually ‘seen’ the object for themselves.’

Head of Glasgow’s Optic Group Prof Miles Padgett said in a statement that low-light imaging techniques underpinned by the process could be used to image fragile materials that can be damaged by intense light.