Phase coherent splitting of Bose-Einstein condensates with an integrated magnetic grating

TL;DR

This paper demonstrates phase coherent splitting of Bose-Einstein condensates using an integrated magnetic grating on a chip, enabling precise control of diffraction and observation of interference patterns.

Contribution

It introduces a novel method of splitting BECs with a micro-fabricated magnetic grating, achieving controlled diffraction and phase coherence.

Findings

Successful phase coherent splitting of BECs using magnetic gratings

Reproducible interference patterns observed after expansion

Precise control of diffraction via integrated conductors

Abstract

We report the phase coherent splitting of Bose-Einstein condensates by means of a phase grating produced near the surface of a micro-electronic chip. A lattice potential with a period of $4\mu$m is generated by the superposition of static and oscillating magnetic fields. Precise control of the diffraction is achieved by controlling the currents in the integrated conductors. The interference of overlapping diffraction orders is observed after 8ms of propagation in a harmonic trap and subsequent ballistic expansion of the atomic ensemble. By analyzing the interference pattern we show a reproducible phase relation between the diffraction orders with an uncertainty given by the resolution of the diffraction grating.