6533b82cfe1ef96bd128f555

RESEARCH PRODUCT

Precision measurement of spin-dependent interaction strengths for spin-1 and spin-2 87Rb atoms

Artur WideraSimon FoellingImmanuel BlochTatjana GerickeFabrice GerbierOlaf Mandel

subject

PhysicsOptical latticeSpin statesFOS: Physical sciencesGeneral Physics and Astronomy01 natural sciences3. Good health010305 fluids & plasmasCondensed Matter - Other Condensed Mattersymbols.namesakeUltracold atom[PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other]0103 physical sciencesAtomsymbolsAntiferromagnetismAtomic physics010306 general physicsHamiltonian (quantum mechanics)Ground stateHyperfine structureOther Condensed Matter (cond-mat.other)

description

We report on precision measurements of spin-dependent interaction-strengths in the 87Rb spin-1 and spin-2 hyperfine ground states. Our method is based on the recent observation of coherence in the collisionally driven spin-dynamics of ultracold atom pairs trapped in optical lattices. Analysis of the Rabi-type oscillations between two spin states of an atom pair allows a direct determination of the coupling parameters in the interaction hamiltonian. We deduce differences in scattering lengths from our data that can directly be compared to theoretical predictions in order to test interatomic potentials. Our measurements agree with the predictions within 20%. The knowledge of these coupling parameters allows one to determine the nature of the magnetic ground state. Our data imply a ferromagnetic ground state for 87Rb in the f=1 manifold, in agreement with earlier experiments performed without the optical lattice. For 87Rb in the f=2 manifold the data points towards an antiferromagnetic ground state, however our error bars do not exclude a possible cyclic phase.

10.1088/1367-2630/8/8/152https://hal.archives-ouvertes.fr/hal-00116280