Coherence and phase of the Stern-Gerlach interferometer

by Mr. Or Dobkowski

Ben-Gurion University Of The Negev

at Quantum optics seminar

Wed, 14 Oct 2020, 15:00
Sacta-Rashi Building for Physics (54), room 207

Abstract

Zoom Link: https://us02web.zoom.us/j/88695778731

This is a student seminar.

The Stern-Gerlach effect, discovered a century ago, has become a paradigm of quantum mechanics. Surprisingly there has been little evidence that the original scheme with freely propagating atoms exposed to gradients from macroscopic magnets is a fully coherent quantum process. Specifically, no full-loop Stern-Gerlach interferometer (SGI) has been realized with the scheme as envisioned decades ago. Furthermore, several theoretical studies have explained why such an interferometer is a formidable challenge.

Here we demonstrate the first full-loop SGI, based on accurate magnetic fields, originating from an atom chip [1]. We confirm successful splitting and recombination achieved by the magnetic gradient pulses. We present measurements of the coherence length and the momentum coherence width of the wavepackets. We also study the little-known separation phase in an open geometry [2].

The methods we introduced allow for novel interferometric schemes, such as the T^3 SGI interferometer [3], clock interferometry, nested interferometers and more. As the SGI does not require light, it can be operated close to surfaces, and allow probing of surface physics.

[1] Y. Margalit, Z. Zhou, O. Dobkowski, Y. Japha, D. Rohrlich, S. Moukouri and R. Folman, "Realization of a complete Stern-Gerlach interferometer" arXiv:1801.02708 (2018)
[2] O. Dobkowski et. al., Separation phase in atom interferometry, in preparation (2020)
[3] O. Amit, Y. Margalit, O. Dobkowski, Z. Zhou, Y. Japha, M. Zimmermann, M. A. Efremov, F. A. Narducci, E. M. Rasel, W. P. Schleich, and R. Folman "T^3 Stern-Gerlach matter-wave interferometer", Physical Review Letters 123, 083601 (2019).

Created on 10-10-2020 by Folman, Ron (folman)
Updaded on 10-10-2020 by Folman, Ron (folman)