abstract:In quantum mechanics, and especially interferometry, the Heisenberg limit is the optimal rate at which the accuracy of a measurement can scale with the energy used in the measurement. Typically, this is the measurement of a phase (applied to one arm of a beam-splitter) and the energy is given by the number of photons used in an interferometer.
Mario Napolitano of the Institute of Photonic Sciences in Barcelona, Spain, and colleagues have now demonstrated a way to break this so-called Heisenberglimit.
That is the limit imposed by Heisenberg's famous uncertainty principle (which states that the precision of a time measurement is limited by the precision of a corresponding energy measurement).