English
Related papers

Related papers: Bell Correlations in a Bose-Einstein Condensate

200 papers

Entanglement is an essential property of quantum many-body systems. However, its local detection is challenging and was so far limited to spin degrees of freedom in ion chains. Here we measure entanglement between the spins of atoms located…

We study two-body correlations in a many-boson system with a hyperspherical approach, where we can use arbitrary scattering length and include two-body bound states. As a special application we look on Bose-Einstein condensation and…

Condensed Matter · Physics 2009-11-10 O. Sørensen , D. V. Fedorov , A. S. Jensen

We study the thermal quantum correlations and entanglement in spin-1 Bose-Hubbard model with two and three particles. While we use negativity to calculate entanglement, more general non-classical correlations are quantified using a new…

Quantum Physics · Physics 2013-04-01 B. Çakmak , G. Karpat , Z. Gedik

We have observed sub-Poissonian spin correlations generated by collisionally induced spin mixing in a spin-1 Bose-Einstein condensate. We measure a quantum noise reduction of -7 dB (-10 dB corrected for detection noise) below the standard…

Quantum Gases · Physics 2015-05-30 Eva M. Bookjans , Christopher D. Hamley , Michael S. Chapman

We propose a direct, coherent coupling scheme that can create massively entangled states of Bose-Einstein condensed atoms. Our idea is based on an effective interaction between two atoms from coherent Raman processes through a (two atom)…

Condensed Matter · Physics 2009-11-07 M. Zhang , Kristian Helmerson , L. You

Bose-Einstein condensates of $^{87}\mathrm{Rb}$ atoms with a hyperfine spin of 2 are open quantum systems, where the atoms are lost through two-body inelastic collisions. In this dissipation process, a collision channel with total spin of 4…

Quantum Gases · Physics 2026-03-10 Takeshi Takahashi , Hiroki Saito

A recent experiment reported the first violation of a Bell correlation witness in a many-body system [Science 352, 441 (2016)]. Following discussions in this paper, we address here the question of the statistics required to witness Bell…

Every Bose-Einstein condensate is in a highly entangled state, as a consequence of the fact that the particles in a condensate are distributed over space in a coherent way. It is proved that any two regions within a condensate of finite…

Quantum Physics · Physics 2009-11-07 Christoph Simon

We investigate schemes to dynamically create many particle entangled states of a two component Bose-Einstein condensate in a very short time proportional to 1/N where $N$ is the number of condensate particles. For small $N$ we compare exact…

Soft Condensed Matter · Physics 2009-11-07 A. Micheli , D. Jaksch , J. I. Cirac , P. Zoller

An approximate many-body theory incorporating two-body correlations has been employed to calculate low-lying collective multipole frequencies in a Bose-Einstein condensate containing $A$ bosons, for different values of the interaction…

Quantum Gases · Physics 2009-07-21 Anindya Biswas , Tapan Kumar Das

Starting with two weakly-coupled anti-ferromagnetic spinor condensates, we show that by changing the sign of the coefficient of the spin interaction, $U_{2}$, via an optically-induced Feshbach resonance one can create an entangled state…

Statistical Mechanics · Physics 2009-11-11 Michael W. Jack , Makoto Yamashita

These two accompanying papers treat two mode entanglement for systems of identical massive bosons and the relationship to spin squeezing and other quantum correlation effects. Entanglement is a key quantum feature of composite systems where…

Quantum Physics · Physics 2016-01-07 Bryan Dalton , John Goold , Barry Garraway , Margaret Reid

We propose a method to produce entangled states of several particles starting from a Bose-Einstein condensate. In the proposal, a single fast $\pi/2$ pulse is applied to the atoms and due to the collisional interaction, the subsequent free…

Quantum Physics · Physics 2009-11-06 Anders Sorensen , Lu-Ming Duan , Ignacio Cirac , Peter Zoller

We review methods that allow one to detect and characterise quantum correlations in many-body systems, with a special focus on approaches which are scalable. Namely, those applicable to systems with many degrees of freedom, without…

Quantum Physics · Physics 2023-09-28 Irénée Frérot , Matteo Fadel , Maciej Lewenstein

Using criteria based on superselection rules, we analyze the quantum correlations between the two condensate modes of the Bose-Einstein condensate interferometer of Egorov et al. [Phys. Rev. A 84, 021605 (2011)]. In order to determine the…

Quantum Physics · Physics 2024-12-13 B. Opanchuk , L. Rosales-Zárate , R. Y. Teh , B. J. Dalton , A. Sidorov , P. D. Drummond , M. D. Reid

Entanglement is at the core of quantum information processing and may prove essential for quantum speed-up. Inspired by both theoretical and experimental studies of spin-momentum coupling in systems of ultra-cold atoms, we investigate the…

Quantum Physics · Physics 2020-10-29 Sumit Suresh Kale , Yijue Ding , Yong P. Chen , Bretislav Friedrich , Sabre Kais

While the interest in multipartite nonlocality has grown in recent years, its existence in large quantum systems is difficult to confirm experimentally. This is mostly due to the inadequacy of standard multipartite Bell inequalities to…

Few-body correlations often express the distinguishing characteristic features of a many-body system. This thesis studies such correlations within dilute Bose-Einstein condensates in the case of arbitrary negative s-wave scattering length.…

Soft Condensed Matter · Physics 2007-05-23 H. H. Sorensen

As demand for quantum technologies increases, so does the need to generate and classify non-classical correlations in complex many-body systems. We introduce a simple and versatile method for creating and certifying entanglement and…

Quantum Physics · Physics 2026-03-23 Marcin Płodzień , Jan Chwedeńczuk

Recent years have witnessed revolutionary improvement in the production, manipulation, characterization and quantification of multiatom (multiqubit) states - because of their promising applications in high precision atomic clocks, atomic…

Quantum Physics · Physics 2011-01-04 A. R. Usha Devi , Sudha