We report Bose-Einstein condensation of weakly bound 6Li2 molecules in a crossed optical trap near Feshbach resonance. measure molecule-molecule scattering length 170(+100)(-60) nm at 770 G, good agreement with theory. study the 2D expansion cloud and show deviation from hydrodynamic behavior BEC-BCS crossover region.

We consider the superfluid phase transition that arises when a Feshbach resonance pairing occurs in dilute Fermi gas. apply our theory to specific potassium ((40)K), and find for achievable experimental conditions, is possible at high critical temperature of about 0.5T(F). Observation superfluidity this regime would provide opportunity experimentally study crossover from weakly coupled fermions Bose-Einstein condensation strongly bound composite bosons.

Combining the measured binding energies of four most weakly bound rovibrational levels 87Rb2 molecule with results two other recent high-precision experiments, we obtain exceptionally strong constraints on atomic interaction parameters in a highly model independent analysis. The comparison (85)Rb and (87)Rb data, where isotopes are related by mass scaling procedure, plays crucial role. We predict scattering lengths, clock shifts, Feshbach resonances an unprecedented level accuracy. Two occur...

We report on the observation of Feshbach resonances in an ultracold mixture two fermionic species, $^{6}\mathrm{Li}$ and $^{40}\mathrm{K}$. The experimental data are interpreted using a simple asymptotic bound state model full coupled channels calculations. This unambiguously assigns observed terms various $s$- $p$-wave molecular states fully characterizes ground-state scattering properties any combination spin states.

The h-index has received an enormous attention for being indicator that measures the quality of researchers and organizations. We investigate to what degree authors can inflate their through strategic self-citations with help a simulation. extended Burrell's publication model procedure placing self-citations, following three different strategies: random self-citation, recent h-manipulating self-citations. results show considerably propose q-index as how strategically author placed which...

We create weakly bound Li2 molecules from a degenerate two component Fermi gas by sweeping magnetic field across Feshbach resonance. The atom-molecule transfer efficiency can reach 85% and is studied as function of initial temperature. bosonic remain trapped for 0.5 s their temperature within factor 2 the Bose-Einstein condensation A thermodynamical model reproduces qualitatively experimental findings.

We investigate the strongly interacting regime in an optically trapped 6Li Fermi mixture near a Feshbach resonance. The resonance is found at 800(40) G good agreement with theory. Anisotropic expansion of gas interpreted by collisional hydrodynamics. observe unexpected and large shift (80 G) between peak both maximum atom loss change sign interaction energy.

We report on experimental evidence of universality in ultracold 7Li atoms' three-body recombination loss the vicinity a Feshbach resonance. observe minimum and an Efimov resonance regions positive negative scattering lengths, respectively, which are connected through pole Both observed features lie deeply within range validity universal theory, we find that relations between their properties, i.e., widths locations, excellent agreement with theoretical predictions.

We report the observation of three $p$-wave Feshbach resonances $^{6}\mathrm{Li}$ atoms in lowest hyperfine state $f=1∕2$. The positions are good agreement with theory. study lifetime cloud vicinity and show that, depending on spin states, two- or three-body mechanisms at play. In case dipolar losses, we observe a nontrivial temperature dependence that is well explained by simple model.

We investigate three-body recombination loss across a Feshbach resonance in gas of ultracold 7Li atoms prepared the absolute ground state and perform comparison with previously reported results different nuclear-spin [N. Gross, Phys. Rev. Lett. 103, 163202 (2009)]. extend universality to state. show that positions widths minima Efimov resonances are identical for both states which indicates short-range physics is independent.

We derive a theory of superfluidity for dilute Fermi gas that is valid when scattering resonances are present. The treatment resonance in many-body atomic physics requires novel mean-field approach starting from an unconventional microscopic Hamiltonian. equations incorporate the physics, and solutions to these reproduce energy-dependent properties. This describes high-${T}_{c}$ behavior system, predicts value ${T}_{c}$ significant fraction temperature. It shown this does not break down...

In a recent experiment, Feshbach scattering resonance was exploited to observe Ramsey fringes in 85Rb Bose-Einstein condensate. The oscillation frequency corresponded the binding energy of molecular state. We show that observations are remarkably consistent with predictions field theory which arise from oscillations between atoms and molecules.

We precisely measured the binding energy of a molecular state near Feshbach resonance in $^{85}$Rb Bose-Einstein condensate (BEC). Rapid magnetic field pulses induced coherent atom-molecule oscillations BEC. oscillation frequency as function B-field and fit data to coupled-channels model. Our analysis constrained position [155.041(18) G], width [10.71(2) background scattering length [-443(3) a$_0$] yielded new values for $v_{DS}$, $v_{DT}$, $C_6$. These results improved our estimate...

We study the widths of interspecies Feshbach resonances in a mixture fermionic quantum gases 6Li and 40K. develop model to calculate width position all available for system. Using model, we select optimal resonance {6}Li/{40}K mixture. Experimentally, obtain asymmetric Fano line shape elastic cross section by measuring distillation rate atoms from potassium-rich 6Li/{40}K as function magnetic field. This provides us with first experimental determination this mixture, DeltaB=1.5(5) G. Our...

In an atomic Bose-Einstein condensate quenched to the unitary regime, we predict sequential formation of a significant fraction condensed pairs and triples. At short distances, demonstrate two-body Efimovian character triples, respectively. As system evolves, their size becomes comparable interparticle distance, such that many-body effects become significant. The structure triples depends on Efimov states compared with density scales. Unexpectedly, find universal in limit where these scales...

This work studies pulse based variational quantum algorithms (VQAs), which are designed to determine the ground state of a mechanical system by combining classical and hardware. In contrast more standard gate methods, methods aim directly optimize laser pulses interacting with qubits, instead using some parametrized circuit. Using mathematical formalism optimal control, these optimized. method has been used in computing for implementations, but only recently proposed full optimization VQAs....

We investigate the robustness of two-qubit gates to deviations experimental controls, on a neutral atom platform utilizing Rydberg states. construct robust CZ - employing techniques from quantum optimal control that retain high Bell state fidelity $F > 0.999$ in presence significant coupling strength state. Such can arise laser intensity noise and atomic motion an inhomogeneous field. also discuss methods mitigate errors due detuning. The designed pulses operate timescales are short compared...

We resolve the unexpected and long-standing disagreement between experiment theory in Efimovian three-body spectrum of $^{7}\mathrm{Li}$, commonly referred to as lithium few-body puzzle. Our results show that discrepancy arises out presence strong nonuniversal spin-exchange interactions, which enact an effective inflation universal Efimov spectrum. This conclusion is obtained from a thorough numerical solution quantum mechanical problem, including precise interatomic interactions all spin...

On the basis of recently measured ${\mathrm{Rb}}_{2}$ bound-state energies and continuum properties, we predict magnetically induced Feshbach resonances in collisions ultracold rubidium atoms. The make it possible to control sign magnitude effective particle-particle interaction a Rb Bose-Einstein condensate by tuning bias magnetic field. For case ${}^{85}\mathrm{Rb}$ they occur at field values range where these atoms can be magnetostatically trapped. ${}^{87}\mathrm{Rb}$ are predicted...

We present a description of the behavior superfluid gas fermions in presence Feshbach resonance over complete range magnetic field detunings. Starting from Hamiltonian, we exploit functional method to describe continuous Bardeen-Cooper-Schrieffer Bose-Einstein condensation type superfluidity. Our results show an ability for system exhibit high critical temperature comparable Fermi temperature. The are derived manner that is shown be consistent with underlying microscopic scattering physics.

Ultracold atomic gases have been used extensively in recent years to realize textbook examples of condensed matter phenomena. Recently, phase transitions ordered structures predicted for highly excited, 'frozen' Rydberg atoms. Such crystals are a model dilute metallic solids with tunable lattice parameters, and provide access wide variety fundamental We investigate theoretically how such can be created four distinct cold systems, by using tailored laser-excitation the presence strong...

Symmetry-breaking phase transitions are central to our understanding of states matter. When a continuous symmetry is spontaneously broken, new excitations appear that tied fluctuations the order parameter. In superconductors and fermionic superfluids, amplitude can fluctuate independently, giving rise two distinct collective branches. However, difficult both generate measure, as they do not couple directly density fermions have only been observed indirectly date. Here, we excite oscillations...

We predict a direct and observable signature of the superfluid phase in quantum Fermi gas, temperature regime already accessible current experiments. apply theory resonance superfluidity to gas confined harmonic potential demonstrate that significant increase density will be observed vicinity trap center.

Feshbach resonances are commonly described by a single-resonance model, and open-channel not taken into account explicitly. However, an resonance near threshold limits the range of validity this model. Such situation exists when background scattering length is much larger than interatomic potential. The introduces strong effects included in description. We derive easy-to-use analytical model that takes both resonance. apply our to $^{85}\mathrm{Rb}$, which has large length, show agreement...