单玻色气体中的二体和三体接触。

Two- and three-body contacts in the unitary Bose gas.

机构信息

Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, UK.

Department of Physics, MIT-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.

出版信息

Science. 2017 Jan 27;355(6323):377-380. doi: 10.1126/science.aai8195. Epub 2017 Jan 26.

DOI:10.1126/science.aai8195

PMID:28126813

Abstract

In many-body systems governed by pairwise contact interactions, a wide range of observables is linked by a single parameter, the two-body contact, which quantifies two-particle correlations. This profound insight has transformed our understanding of strongly interacting Fermi gases. Using Ramsey interferometry, we studied coherent evolution of the resonantly interacting Bose gas, and we show here that it cannot be explained by only pairwise correlations. Our experiments reveal the crucial role of three-body correlations arising from Efimov physics and provide a direct measurement of the associated three-body contact.

摘要

在由两两接触相互作用控制的多体系统中，广泛的可观测量由单个参数——二体接触联系在一起，该参数量化了两粒子相关性。这一深刻的认识改变了我们对强相互作用费米气体的理解。我们使用拉姆齐干涉测量法研究了共振相互作用玻色气体的相干演化，并在本文中表明，仅用两体相关性无法解释这一现象。我们的实验揭示了源自 Efimov 物理的三体相关性的关键作用，并提供了对相关三体接触的直接测量。