Can a falling atom make a noise in two forests at the same time?

Abstract

The measurable consequences of the tunneling particle's being `in two places at one time' is investigated. A double magneto-optical trap geometry is used to transfer the atoms into a magnetic trap in an extremely high vacuum region, where an acousto-optically modulated beam from a 5-W solid state laser is used to velocity-select the atoms in one dimension and form a tunable, time-variable tunnel barrier. The time spend by the tunneling atoms in different regions of space is measured by optical pumping and Raman beams as probes. The resulting complex times and their implications for optical measurements on tunneling atoms are described.