A Bose-Einstein condensate is used as an atomic source for a high precision
sensor. A 5×106 atom F=1 spinor condensate of 87Rb is released
into free fall for up to 750ms and probed with a Mach-Zehnder atom
interferometer based on Bragg transitions. The Bragg interferometer
simultaneously addresses the three magnetic states, ∣mf=1,0,−1⟩, facilitating a simultaneous measurement of the acceleration due
to gravity with an asymptotic precision of 2.1×10−9Δg/g and
the magnetic field gradient to a precision 8pT/m