Citation for published item:wolonyD eter uF nd qregoryD hilip hF nd tiD honghu nd vuD fo nd u¤ oppingerD wi h el F nd ve ueurD gF uth nd fl kleyD g roline vF nd rutsonD teremy wF nd gornishD imon vF @PHIRA 9gre tion of ultr old VU IQQgs mole ules in the rovi r tion l ground st teF9D hysi l review lettersFD IIQ @PSAF pF PSSQHIF Further information on publisher's website:httpXGGdxFdoiForgGIHFIIHQG hys evvettFIIQFPSSQHI Publisher's copyright statement:Reprinted with permission from the American Physical Society: Physical Review Letters 113, 255301 c 2014 by the American Physical Society. Readers may view, browse, and/or download material for temporary copying purposes only, provided these uses are for noncommercial personal purposes. Except as provided by law, this material may not be further reproduced, distributed, transmitted, modi ed, adapted, performed, displayed, published, or sold in whole or part, without prior written permission from the American Physical Society.Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. We report the creation of a sample of over 1000 ultracold 87 Rb 133 Cs molecules in the lowest rovibrational ground state, from an atomic mixture of 87 Rb and 133 Cs, by magnetoassociation on an interspecies Feshbach resonance followed by stimulated Raman adiabatic passage (STIRAP). We measure the binding energy of the RbCs molecule to be hc × 3811.576ð1Þ cm −1 and the jv 00 ¼ 0; J 00 ¼ 0i to jv 00 ¼ 0; J 00 ¼ 2i splitting to be h × 2940.09ð6Þ MHz. Stark spectroscopy of the rovibrational ground state yields an electric dipole moment of 1.225(3)(8) D, where the values in parentheses are the statistical and systematic uncertainties, respectively. We can access a space-fixed dipole moment of 0.355(2)(4) D, which is substantially higher than in previous work.

We report the production of 87 RbCs Feshbach molecules in a crossed-beam dipole trap. A mixture of 87 Rb and 133 Cs is cooled close to quantum degeneracy before an interspecies Feshbach resonance at 197 G is used to associate up to ∼ 5000 molecules with a temperature of ∼ 300 nK. The molecules are confined in the dipole trap with a lifetime of 0.21(1) s, long enough for future experiments exploring optical transfer to the absolute ground state. We have measured the magnetic moment of the Feshbach molecules in a magnetic bias field range between 181 and 185 G to demonstrate the ability to control the character of the molecular state. In addition, we have performed Feshbach spectroscopy in a field range from 0 to 1200 G and located three previously unobserved resonances at high magnetic fields.

We investigate numerically the collisions of two distinguishable quantum matter-wave bright solitons in a one-dimensional harmonic trap. We show that such collisions can be used to generate mesoscopic Bell states which can reliably be distinguished from statistical mixtures. Calculation of the relevant s-wave scattering lengths predicts that such states could potentially be realized in quantum-degenerate mixtures of 85 Rb and 133 Cs. In addition to fully quantum simulations for two distinguishable two-particle solitons, we use a mean-field description supplemented by a stochastic treatment of quantum fluctuations in the soliton's center of mass: We demonstrate the validity of this approach by comparison to a mathematically rigorous effective potential treatment of the quantum many-particle problem. Generating quantum entanglement between mesoscopic objects over mesoscopic distances allows exploration of a fascinating "middle-ground" between quantum and classical physics [1,2], and promises significant advances in quantum-enhanced interferometry [3]. The high degree of experimental control offered by quantum-degenerate gases makes them an ideal platform with which to explore such multi-particle entanglement [4,5]. From a fundamental perspective, the creation of maximally-entangled many-particle Bell states in quantum-degenerate gases presents an intriguing proposition. The generation of similar macroscopic Bell states of many photons is an area of current theoretical and experimental research [6,7]. In addition to their inherent fundamental interest, such states are of potential application as a resource in quantum information [7].Previously, the scattering of quantum bright matterwave solitons [8][9][10][11][12][13][14][15][16][17] in quasi-one-dimensional (1D) trapping geometries has been suggested as a way to create mesoscopic entangled states in single-species BoseEinstein condensates (BECs) [13,18,19]. In this Letter we consider a dual-species BEC [20,21] where |A, B (|B, A ) signifies that the BEC A is on the left (right) and the BEC B is on the right (left). In particular, we show that a favorable combination of interand intra-species s-wave scattering lengths means that such states may be realized using 85 Rb and 133 Cs mixtures. We also show that the interference properties of these bright-soliton Bell states distinguish them from statistical mixtures. In contrast to the Bell ground states associated with double-well potentials, our collisionallygenerated Bell states are robust to the presence of asymmetries. While distinguishable solitons are essential to produce Bell states, entanglement generation for solitons of the same species was investigated in [13].For our quasi-1D system, we consider an experimentally motivated harmonic confinement ω = 2πf . Mixtures of ultracold gases can be confined in a common optical trap with the same trap frequencies [24], yieldingwhere m A (m B ) is the atomic mass of species A (B); the interactions g = hf ⊥ a are set by the scattering lengths a and the perpendicular tra...

We consider the possibilities for producing ultracold mixtures of K and Cs and forming KCs molecules by magnetoassociation. We carry out coupled-channel calculations of the interspecies scattering length for 39 KCs, 41 KCs and 40 KCs and characterize Feshbach resonances due to s-wave and d-wave bound states, with widths ranging from below 1 nG to 5 G. We also calculate the corresponding bound-state energies as a function of magnetic field. We give a general discussion of the combinations of intraspecies and interspecies scattering lengths needed to form low-temperature atomic mixtures and condensates and identify promising strategies for cooling and molecule formation for all three isotopic combinations of K and Cs.

Citation for published item:flkleyD groline vF nd ve ueurD gF uth nd rutsonD teremy wF nd wgrronD hniel tF nd u¤ oppingerD wihel F nd ghoD rungEen nd tenkinD hniel vF nd gornishD imon vF @PHIQA 9peshh resonnes in ultrold VSF9D hysil review eFD VU @QAF HQQTIIF Further information on publisher's website: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. 85 Rb. Seven of the resonances are in the ground-state channel (f,m f ) = (2,+2) + (2,+2) and nine are in the excited-state channel (2,−2) + (2,−2). We find a wide resonance at high field in each of the two channels, offering possibilities for the formation of larger 85 Rb condensates and studies of few-body physics. A detailed coupled-channel analysis is presented to characterize the resonances and also provides an understanding of the inelastic losses observed in the excited-state channel. In addition we have confirmed the existence of one narrow resonance in a (2,+2) + (3,+3) spin mixture.