Holger Müller, University of California, Berkeley
Abstract
De Broglie's matter wave hypothesis describes particles as oscillators at the Compton frequency mc^2/h, where m is the particle's mass, c the speed of light, and h the Planck constant [1]. We use these oscillations as clocks of superb resolution in a series of of atom-interferometry experiments: (i) A test of the gravitational redshift at an accuracy of 7 parts per billion [2] that provides some of our most precise bounds tests of general relativity in the framework of the standard model extension [3]; (ii) A proposed gravitational Aharonov-Bohm experiment, which will reveal the gravitational redshift of the Compton frequency even in absence of a gravitational force [4]; (iii) A matter-wave clock, in which the Compton frequency of a Cs atom (~3x10^25 Hz) is divided into a conveniently measurable frequency range, based on a combination of an atom-interferometer and an optical frequency comb. The clock achieves an accuracy of 4 parts per billion and can serve as a time standard based on mass or vice versa [5]. We will also present the technology of our atom interferometers, which currently feature the largest enclosed area worldwide [6].