Quantum entanglement is like two dancers always performing perfectly synchronized steps, even on different continents. Such a duet was previously only achieved in laboratory refrigerators. Now physicists have staged it in a flat crystal of boron nitride at room temperature, pairing the spin of an electron with the spin of a carbon-13 nucleus. To prevent the rhythm-disrupting crowd of atoms from spoiling the dance, they used 'dynamic decoupling'—a technique that isolates the pair from outside noise. The sync lasted 38 microseconds — an eternity on the quantum scale.
The nuclear spin served as quantum memory, boosting the sensitivity of magnetic sensors to the point of distinguishing individual molecules. Correlation spectroscopy and control of quantum disorder, entropy, played a key role. An unexpected twist: the entangled pair's room-temperature stability turned out to be sufficient for working inside a living cell. Biologists are already eyeing this tool for observing molecular processes.
Entangled particles can exist in two states at once — physicists call this superposition. Only a measurement forces them to pick one.
Sensors based on entangled particles resemble a tricorder from Star Trek, a pocket matter analyzer that distinguishes atoms.