近日，日本东京科学研究所Mikio Kozuma团队报道了玻色-爱因斯坦凝聚体中爱因斯坦-德哈斯效应的观测。该研究于2026年1月22日发表在《科学》杂志上。

爱因斯坦-德哈斯效应是一种角动量从微观自旋向宏观刚体机械旋转转移的现象。

研究组在自旋-偶极玻色-爱因斯坦凝聚体中观测到爱因斯坦-德哈斯效应，其中本征的磁偶极-偶极相互作用介导了角动量从原子自旋向量子流体集体环流的相干转移。退极化的自旋分量呈现出环状密度分布，通过物质波干涉技术证实其为量子化涡旋，揭示了自旋角动量与轨道角动量之间的相干转换。这一发现为探索具有破缺手征对称性的基态相、自旋纹理与质量环流，以及偶极量子气体中的巴奈特效应开辟了新路径。

附：英文原文

Title: Observation of the Einstein–de Haas effect in a Bose–Einstein condensate

Author: Hiroki Matsui, Yuki Miyazawa, Ryoto Goto, Chihiro Nakano, Yuki Kawaguchi, Masahito Ueda, Mikio Kozuma

Issue&Volume: 2026-01-22

Abstract: The Einstein–de Haas effect is a phenomenon in which angular momentum is transferred from microscopic spins to mechanical rotation of a macroscopic rigid body. We report an observation of the Einstein–de Haas effect in a spinor-dipolar Bose–Einstein condensate, in which the intrinsic magnetic dipole-dipole interaction mediates coherent transfer of angular momentum from atomic spins to collective circulation of a quantum fluid. The depolarized spinor components displayed ring-shaped density distributions that were confirmed as quantized vortices through matter-wave interferometry, revealing a coherent conversion between spin and orbital angular momentum. This observation opens a pathway to exploring ground-state phases with broken chiral symmetry, spin textures, and mass circulation, as well as the Barnett effect in dipolar quantum gases.

DOI: adx2872

Source: https://www.science.org/doi/10.1126/science.adx2872