Physical Review A
“Superluminal” tunneling as a weak measurement effect
D. Sokolovski, ALFRED Z. MSEZANE, Vasily R. Shaginyan
Abstract
We exploit the analogy between the transfer of a pulse across a scattering medium and Aharonov's weak measurements to resolve the long standing paradox between the impossibility to exceed the speed of light and the seemingly ``superluminal'' behavior of a tunneling particle in the barrier or a photon in a ``fast-light'' medium. We demonstrate that superluminality occurs when the value of the duration $\ensuremath{\tau}$ spent in the barrier is uncertain, whereas when $\ensuremath{\tau}$ is known accurately, no superluminal behavior is observed. In all cases only subluminal durations contribute to the transmission which precludes faster-than-light information transfer, as observed in a recent experiment.