title: Measuring energy differences by BEC interferometry on a chip.
abstract: We investigate the use of a Bose-Einstein condensate trapped on an atom chip for making interferometric measurements of small energy differences. We measure and explain the noise in the energy difference of the split condensates, which derives from statistical noise in the number difference. We also consider systematic errors. A leading effect is the variation of the rf magnetic field in the trap with distance from the wires on the chip surface. This can produce energy differences that are comparable with those due to gravity.
authors.affiliation: Centre for Cold Matter, Blackett Laboratory, Imperial College, Prince Consort Road, London SW7 2AZ, UK.
authors.forename: Florian
authors.initials: F
authors.lastname: Baumgärtner
authors.forename: R J
authors.initials: RJ
authors.lastname: Sewell
authors.forename: S
authors.initials: S
authors.lastname: Eriksson
authors.forename: I
authors.initials: I
authors.lastname: Llorente-Garcia
authors.forename: Jos
authors.initials: J
authors.lastname: Dingjan
authors.forename: J P
authors.initials: JP
authors.lastname: Cotter
authors.forename: E A
authors.initials: EA
authors.lastname: Hinds