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arXiv · 1611.08430

Measuring finite-range phase coherence in an optical lattice using Talbot interferometry

Bodhaditya Santra·Christian Baals·Ralf Labouvie·Aranya B. Bhattacherjee·Axel Pelster·Herwig Ott
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Abstract

One of the important goals of present research is to control and manipulate coherence in a broad variety of systems, such as semiconductor spintronics, biological photosynthetic systems, superconducting qubits and complex atomic networks. Over the past decades interferometry of atoms and molecules has proven to be a powerful tool to explore coherence. Here we demonstrate a near-field interferometer based on the Talbot effect, which allows to measure finite-range phase coherence of ultracold atoms in an optical lattice. We apply this interferometer to study the build-up of phase coherence after a quantum quench of a Bose-Einstein condensate residing in a one-dimensional optical lattice. Our technique of measuring finite-range phase coherence is generic, easy to adopt, and can be applied in practically all lattice experiments without further modifications.

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Bodhaditya Santra, Christian Baals, Ralf Labouvie, Aranya B. Bhattacherjee, Axel Pelster, Herwig Ott. 2016-11-25. Measuring finite-range phase coherence in an optical lattice using Talbot interferometry. https://doi.org/10.1038/ncomms15601

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