Related Experiment Video
Updated: Aug 18, 2026

Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Nonreciprocal and Long-Range Three-Body Interactions in Bose-Einstein Condensates Induced by Optical Feedback
Yi-Qing Zhang1, Liang-Jun He1, Han Pu2
1Xi'an Jiaotong University, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, and Shaanxi Key Laboratory of Quantum Information and Quantum Optoelectronic Devices, School of Physics, Xi'an 710049, People's Republic of China.
None:
We propose generating atom-atom three-body interactions in quantum gases by placing a quasi-two-dimensional Bose-Einstein condensate in front of two reflecting mirrors and illuminating it with dichromatic laser beams. These pumping fields traverse the condensate twice, thereby inducing a feedback effect on the atoms. We demonstrate that this optical feedback gives rise to an effective three-body interaction with unique long-range and nonreciprocal properties. Because of its long-range nature, this three-body interaction can give rise to various stable stationary droplet cluster states, as well as a distinct ring state that emerges through a purely self-organizing process. Furthermore, we show that the nonreciprocal nature of this interaction can lead to remarkable self-acceleration of the condensate. Additionally, our scheme offers a highly controllable setting, where pairwise two-body interactions can be tuned to vanish. This flexibility provides a promising route for exploring exotic physics associated with multibody interactions.
Related Concept Videos
¹H NMR: Long-Range Coupling
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.
Atomic Nuclei: Nuclear Relaxation Processes
Nuclear Overhauser Enhancement (NOE)
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
Spin–Spin Coupling Constant: Overview
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must have a...
NMR Spectroscopy: Spin–Spin Coupling

