Atom Interferometers with Scalable Enclosed Area

Bloch oscillations (i.e., coherent acceleration of matter waves by an optical lattice) and Bragg diffraction are integrated into light-pulse atom interferometers with large momentum splitting between the interferometer arms, and hence enhanced sensitivity. Simultaneous acceleration of both arms in the same internal states suppresses systematic effects, and simultaneously running a pair of interferometers suppresses the effect of vibrations. Ramsey-Bordé interferometers using four such Bloch-Bragg-Bloch beam splitters exhibit 15% contrast at $24\hslash k$ splitting, the largest so far ($\hslash k$ is the photon momentum); single beam splitters achieve $88\hslash k$. The prospects for reaching 100 s of $\hslash k$ and applications such as gravitational wave sensors are discussed.

Figure 1

Left: space-time diagram of simultaneous conjugate Ramsey-Bordé BBB-interferometers. 1: Dual optical lattice; 2: single Bragg beam splitter; 3: quadruple optical lattice; 4: dual Bragg beam splitter; (a)–(d): outputs. The dashed lines indicate trajectories that do not interfere. Right: plotting the outputs of the interferometers versus one another draws an ellipse.

Figure 2

Trajectories of the atom (a), laser frequencies (b), and laser intensities (c) during a BBB beam splitter.

Figure 3

Setup. Arbitrary waveform generator (AWG). $\lambda /4$: quarter-wave retardation plate. Double-balanced mixer (DBM).

Figure 4

Time-of-flight sheet of the output of an $88\hslash k$ beam splitter.

Figure 5

Ellipses from simultaneous conjugate interferometers with BBB beam splitters. Total momentum transfer, Bragg diffraction order $n$, Bloch oscillation number $N$, and contrast $C$ [29] are stated. All graphs are plotted using the same scale.