All posts tagged: optical physics

Researchers discover a new way to control light in empty space

Researchers discover a new way to control light in empty space

Published by Jenni Sidey

Light does not usually surprise people. It travels, it reflects, it bends. In labs, researchers can twist it into more exotic forms, but that has often required special surfaces, unusual materials, or intense focusing with powerful optics. This time, the surprise came from free space itself. Scientists at the University of East Anglia, working with colleagues in South Africa, report that light can develop a kind of handedness as it moves through empty space, without mirrors, materials, or special lenses shaping it along the way. The work, published in Light: Science & Applications, points to a new way of controlling light by using its internal geometry. That matters because handedness, also called chirality, sits at the center of chemistry and biology. Many molecules, including some used in medicines, come in left- and right-handed forms that can look nearly identical while behaving very differently in the body. Schematic of the experimental setup depicting (a) the generation and (b) detection components. (c) Experimentally recorded polarization intensities for H, V, D, A, R and L for 3 separate …

MIT’s self-organizing laser revolutionizes 3D imaging of the brain’s protective barrier

MIT’s self-organizing laser revolutionizes 3D imaging of the brain’s protective barrier

Published by Jenni Sidey

At high power, laser light inside a multimode optical fiber is supposed to misbehave. The beam usually breaks into a noisy, scattered pattern as the light ricochets through many paths at once. But MIT researchers found a case where that expectation fails. Push the system close to its limit, line the beam up just right, and the optical mess can collapse into a tightly focused, self-organized “pencil beam.” That beam, the team reports, can do more than tidy up a physics problem. In experiments on a human model of the blood-brain barrier, it produced 3D images about 25 times faster than a standard approach. This was achieved while keeping similar cellular-level detail. The work appears in Nature Methods. “The common belief in the field is that if you crank up the power in this type of laser, the light will inevitably become chaotic. But we proved that this is not the case. We followed the evidence, embraced the uncertainty, and found a way to let the light organize itself into a novel solution for bioimaging,” …

New optical trick pulls hidden quantum signals out of background noise

New optical trick pulls hidden quantum signals out of background noise

Published by Jenni Sidey

Bright background light can do more than clutter a quantum experiment. It can wash out the very features that make quantum systems useful in the first place. That is the problem a team at the Institut national de la recherche scientifique, or INRS, set out to tackle. Working with light particles called photons, the researchers built a way to sift out meaningful quantum signals even when those signals are buried under heavy optical noise. Their results, published in Science Advances, point to a simpler and more energy-efficient route for keeping quantum information intact in messy, real-world conditions. The work came from the group of Professor José Azaña, in collaboration with Professor Roberto Morandotti’s team. It was carried out by Benjamin Crockett during his PhD at the INRS Énergie Matériaux Télécommunications Research Centre. Crockett has since moved to the University of British Columbia as a Banting postdoctoral fellow. Quantum technologies depend on detecting the properties carried by single photons. That sounds manageable in a carefully controlled lab. It becomes much harder when the photon you care …