Alexander Khramov

Quantum Degenerate Mixture of Ytterbium and Lithium Atoms

We have produced a quantum degenerate mixture of fermionic alkali-metal {sup 6}Li and bosonic spin-singlet {sup 174}Yb gases. This was achieved using sympathetic cooling of lithium atoms by evaporatively cooled ytterbium atoms in a far-off-resonant optical dipole trap. We observe the coexistence of Bose-condensed (T/T{sub c}{approx_equal}0.8) {sup 174}Yb with 2.3x10{sup 4} atoms and Fermi degenerate (T/T{sub F}{approx_equal}0.3) {sup 6}Li with 1.2x10{sup 4} atoms. Quasipure Bose-Einstein condensates of up to 3x10{sup 4} {sup 174}Yb atoms can be produced in single-species experiments. Our results mark a significant step toward studies of few- and many-body physics with mixtures of alkali-metal and alkaline-earth-metal-like atoms, and for the production of paramagnetic polar molecules in the quantum regime. Our methods also establish a convenient scheme for producing quantum degenerate ytterbium atoms in a 1064 nm optical dipole trap.

Sympathetic cooling in an optically trapped mixture of alkali and spin-singlet atoms.

We report on the realization of a stable mixture of ultracold lithium and ytterbium atoms confined in a far-off-resonance optical dipole trap. We observe sympathetic cooling of 6Li by 174Yb and extract the s-wave scattering length magnitude |a(6Li-174Yb)|=(13±3)a0 from the rate of interspecies thermalization. Using forced evaporative cooling of 174Yb, we achieve reduction of the 6Li temperature to below the Fermi temperature, purely through interspecies sympathetic cooling.

Production of quantum degenerate mixtures of ytterbium and lithium with controllable inter-species overlap

Department of Physics, University of Washington, Seattle, Washington 98195, USA(Dated: January 23, 2013)Quantum-degenerate mixtures of one-electron and two-electron atoms form the starting point forstudying few- and many-body physics of mass-imbalanced pairs as well as the production of param-agnetic polar molecules. We recently reported the achievement of dual-species quantum degeneracyof a mixture of lithium and ytterbium atoms. Here we present details of the key experimental stepsfor the all-optical preparation of these mixtures. Further, we demonstrate the use of the magneticfield gradient tool to compensate for the differential gravitational sag of the two species and controltheir spatial overlap.I. INTRODUCTION

Laser induced fluorescence of Mg-phthalocyanine in He droplets : Evidence for fluxionality of large H2 clusters at 0.38 K

The formation of Ar and H2 clusters, having up to 900 particles in helium droplets, has been studied via laser induced fluorescence of attached Mg-phthalocyanine (Mg-Pc) molecules. In the experiments, one Mg-Pc molecule in average was added to each He droplet either before or after the cluster species, and the shift of the spectrum of the Mg-Pc molecules was studied as a function of the cluster size. For Ar clusters, about a factor of 2 smaller matrix shift was observed for the late pickup of the Mg-Pc molecules as compared with the prior pickup, indicating that in the former case, the Mg-Pc molecules reside on the surface of the preformed Ar clusters. On the other hand, the spectra of the Mg-Pc molecules attached to H2 clusters are independent of the pickup order, which is consistent with Mg-Pc molecules residing near the center of the H2 clusters in both cases. Therefore H2 clusters remain fluxional in helium droplets at T=0.38 K. No significant differences in the spectra were observed between the para-H2 and ortho-H2 clusters.

Dynamics of Feshbach molecules in an ultracold three-component mixture

We present investigations of the formation rate and collisional stability of lithium Feshbach molecules in an ultracold three-component mixture composed of two resonantly interacting fermionic

Ultracold Heteronuclear Mixture of Ground and Excited State Atoms

{}^{6}

Rovibrational wave-packet manipulation using shaped midinfrared femtosecond pulses

Li spin states and bosonic

Probing the Lyman-alpha transition in antihydrogen

{}^{174}

Ultracold Mixture of Lithium and Metastable Ytterbium Atoms

Yb. We observe long molecule lifetimes (

Ultracold Mixtures of Lithium and Ytterbium

g100