Multi-isotope operation of atom interferometers can enable new practical capabilities such as concurrent and co-located interferometers exhibiting multi-axis or multi-scale-factor measurement, in addition to fundamental studies such as equivalence principle tests. We describe the development of a dual-isotope interferometer based on a continuously laser-cooled atomic beam. In addition, we provide an update on our development of a dualbeam atomic gyroscope using continuous, counterpropagating, 3D-cooled rubidium beams for inertial sensing applications.
Atom interferometers make use of the interference of matter waves for precise measurement of motion. Employing 3D-laser-cooled atoms provides improved fringe contrast, while measuring in a continuous beam architecture provides high-bandwidth measurement, error suppression of time-varying signals, and the elimination of measurement dead time. In this paper, we discuss the initial observation of interference signals in a dual-beam, 3D-cooled atomic beam interferometer architecture. Additionally, we perform initial characterization of the response of the atom interferometer signal to laser intensity and frequency noise.
We report a Mach-Zehnder-type dual-atom-interferometer gyroscope with an interrogation arm of 40-cm length and the interference area up to
1.2cm2. The precise angular alignment of the large-scale separated Raman lasers is demonstrated by seeking the phase intersection of Ramsey-$\mathrm{Bord}\stackrel{\ifmmode \acute{}\else \'{}\fi{}}{\mathrm{e}}$ interferometers after the gravity effect is compensated and by decoupling the velocity dependent cross-talk phase shifts, and applied to build the Mach-Zehnder atom interferometer. Then a compact inertial rotation sensor is realized based on dual large-area Mach-Zehnder atom interferometers by precisely aligning the large-scale separated Raman lasers, in which the coherence is well preserved and the common noise is differentially suppressed. The sensor presents a sensitivity of $1.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}$
rad/s/Hz1/2, and a stability of $9.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}\phantom{\rule{0.16em}{0ex}}\mathrm{rad}/\mathrm{s}$ at 23000 s. The absolute rotation measurement is carried out by adjusting the atomic velocity which corresponds to modulating the scale factor.