Collisional spin transfer in an atomic heteronuclear spinor Bose gas

Fang Fang,Chris H Greene,Katinka Horn,Joshua A Isaacs,Yimeng Wang,L Dalila Robledo-De Basabe,Aaron Smull,Dan M Stamper-Kurn

doi:10.1103/physrevresearch.2.032054

Abstract

We observe spin transfer within a non-degenerate heteronuclear spinor atomic gas comprised of a small $^7$Li population admixed with a $^{87}$Rb bath, with both elements in their $F=1$ hyperfine spin manifolds and at temperatures of 10's of $\mu$K. Prepared in a non-equilibrium initial state, the $^7$Li spin distribution evolves through incoherent spin-changing collisions toward a steady-state distribution. We identify and measure the cross-sections of all three types of spin-dependent heteronuclear collisions, namely the spin-exchange, spin-mixing, and quadrupole-exchange interactions, and find agreement with predictions of heteronuclear $^7$Li-$^{87}$Rb interactions at low energy. Moreover, we observe that the steady state of the $^7$Li spinor gas can be controlled by varying the composition of the $^{87}$Rb spin bath with which it interacts.

Highlights

Collisional spin transfer in an atomic heteronuclear spinor Bose gas Fang Fang,1,* Joshua A
We observe that the steady state of the 7Li spinor gas can be controlled by varying the composition of the 87Rb spin bath with which it interacts
The spin dynamics of a gas of itinerant particles are central to a range of phenomena in atomic and condensed-matter physics

Summary

Rapid Communications

Collisional spin transfer in an atomic heteronuclear spinor Bose gas Fang Fang,1,* Joshua A. We observe spin transfer within a nondegenerate heteronuclear spinor atomic gas comprising a small 7Li population admixed with a 87Rb bath, with both elements in their F = 1 hyperfine spin manifolds. Optical trapping of atomic gases enables the study of spinor Bose and Fermi gases, in which atoms may populate any of the magnetic sublevels within a manifold of fixed total atomic spin [11]. These gases present a controlled medium for studying magnetic ordering, phase transitions, and nonequilibrium spin dynamics.

Rb quadrupole exchange

Rb m

This rate equation ignores possible variations of the Li and

TLi π mRb mLi

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