Observation of Spin-Spin Fermion-Mediated Interactions between Ultracold Bosons.

Interactions in an ultracold boson-fermion mixture are often manifested by elastic collisions. In a mixture of a condensed Bose gas (BEC) and spin polarized degenerate Fermi gas (DFG), fermions can mediate spin-spin interactions between bosons, leading to an effective long-range magnetic interaction analogous to Ruderman-Kittel-Kasuya-Yosida [Phys. Rev.

Publisher's Note: Observation of Optomechanical Strain in a Cold Atomic Cloud [Phys. Rev. Lett. 119, 163201 (2017)].

This corrects the article DOI: 10.1103/PhysRevLett.119.

Observation of Optomechanical Strain in a Cold Atomic Cloud.

We report the observation of optomechanical strain applied to thermal and quantum degenerate ^{87}Rb atomic clouds when illuminated by an intense, far detuned homogeneous laser beam. In this regime the atomic cloud acts as a lens that focuses the laser beam. As a backaction, the atoms experience a force opposite to the beam deflection, which depends on the atomic cloud density profile.