Quantum physicists have uncovered a bizarre phenomenon in which photons appear to spend a “negative” amount of time interacting with atoms before emerging from a cloud of matter. As Homer tells us, Odysseus made an epic journey, against the odds, from Troy to his home in Ithaca. He visited many lands but mostly dwelt with [...]

Scientists have shown that sunlight alone can generate quantum-correlated photons capable of producing “ghost images,” a feat once thought to require stable lasers. Quantum optics experiments typically rely on carefully controlled lasers to create correlated or entangled photon pairs. These photon pairs are produced through a process known as spontaneous parametric down-conversion (SPDC), in…

A team of physicists has uncovered a hidden topological structure within one of the most widely used sources of quantum entanglement. Researchers from the University of the Witwatersrand in South Africa, working together with scientists from Huzhou University, have identified an unexpected property in a widely used quantum optics technique. Experiments that routinely generate entangled [...]