Coherent Delocalization of Atomic Wave Packets in Driven Lattice Potentials

TL;DR

This paper demonstrates that phase-modulated optical lattices induce coherent delocalization of atomic wave packets via intraband transitions, enabling precise gravity measurements through resonance observations.

Contribution

It reports the first observation of Wannier-Stark intraband transitions in a driven optical lattice and uses these resonances for high-precision gravity sensing.

Findings

Resonances occur at integer multiples of the Bloch frequency.

Resonance widths are Fourier-limited up to 2 seconds.

Gravity can be measured with ppm resolution using this method.

Abstract

Atomic wave packets loaded into a phase-modulated vertical optical-lattice potential exhibit a coherent delocalization dynamics arising from intraband transitions among Wannier-Stark levels. Wannier-Stark intraband transitions are here observed by monitoring the in situ wave-packet extent. By varying the modulation frequency, we find resonances at integer multiples of the Bloch frequency. The resonances show a Fourier-limited width for interrogation times up to 2 s. This can also be used to determine the gravity acceleration with ppm resolution.