标题： 通过旋转磁场调节量子气体中的偶极-偶极相互作用 显示英文标题

标题： Tuning the dipole-dipole interaction in a quantum gas with a rotating magnetic field

摘要： 我们通过快速旋转原子偶极子的方向，展示了在镝玻色-爱因斯坦凝聚体中磁偶极-偶极相互作用（DDI）的调节。 偶极平均场能量的可调性表现为飞行时间膨胀后的气体纵横比发生变化。 我们证明，可以使用这种技术调节DDI的大小和符号。 特别是，我们表明存在一个魔法旋转角度，在该角度下平均场DDI可以被消除，并且在该角度下，凝聚体的膨胀动力学接近于非偶极气体所预测的情况。 能够调节DDI的强度为创造奇异的孤子和涡旋态以及不寻常的量子晶格相和外尔超流体开辟了新的途径。 显示英文摘要

摘要： We demonstrate the tuning of the magnetic dipole-dipole interaction (DDI) within a dysprosium Bose-Einstein condensate by rapidly rotating the orientation of the atomic dipoles. The tunability of the dipolar mean-field energy manifests as a modified gas aspect ratio after time-of-flight expansion. We demonstrate that both the magnitude and the sign of the DDI can be tuned using this technique. In particular, we show that a magic rotation angle exists at which the mean-field DDI can be eliminated, and at this angle, we observe that the expansion dynamics of the condensate is close to that predicted for a non-dipolar gas. The ability to tune the strength of the DDI opens new avenues toward the creation of exotic soliton and vortex states as well as unusual quantum lattice phases and Weyl superfluids.