Multiaxis Inertial Sensing with Long-Time Point Source Atom Interferometry

We show that light-pulse atom interferometry with atomic point sources and spatially resolved detection enables multiaxis (two rotation, one acceleration) precision inertial sensing at long interrogation times. Using this method, we demonstrate a light-pulse atom interferometer for ⁸⁷Rb with 1.4 cm peak wave packet separation and a duration of 2T=2.3 s. The inferred acceleration sensitivity of each shot is 6.7×10^-12g, which improves on previous limits by more than 2 orders of magnitude. We also measure Earth's rotation rate with a precision of 200 nrad/s.