We study 1D trapped Bose gases in the strongly interacting regime. The systems are created an optical lattice and subject to a longitudinal periodic potential. Bragg spectroscopy enables us investigate excitation spectrum different regimes. In superfluid phase broad continuum of excitations is observed which calls for interpretation beyond Bogoliubov taking into account effect strong interactions. Mott insulating discrete measured. Both phases compared 3D situation crossover regime from 3D....

We have studied interacting and noninteracting quantum degenerate Fermi gases in a three-dimensional optical lattice. directly image the surface of atoms lattice by turning off adiabatically. Because confining potential, gradual filling transforms system from normal state into band insulator. The dynamics transition insulator to is studied, time scale measured be an order magnitude larger than tunneling Using Feshbach resonance, we increase interaction between two different spin states...

We have studied dissipation in a Bose--Einstein condensed gas by moving blue detuned laser beam through the condensate at different velocities. Strong heating was observed only above critical velocity.

We report on the realization of a trapped one-dimensional Bose gas and its characterization by means measuring lowest lying collective excitations. The quantum degenerate is prepared in 2D optical lattice, we find ratio frequencies compressional (breathing) mode dipole to be (omega(B)/omega(D))(2) approximately 3.1, accordance with Lieb-Liniger mean-field theory. For thermal measure 4. By heating gas, have studied transition between two regimes. number particles attainable experiment kinetic...

We have observed two-particle bound states of atoms confined in a one-dimensional matter waveguide. These exist irrespective the sign scattering length, contrary to situation free space. Using radio-frequency spectroscopy we measured binding energy these dimers as function length and confinement find good agreement with theory. The strongly interacting Fermi gas which create an optical lattice represents realization tunable Luttinger liquid.

We realize and study a strongly interacting two-component atomic Fermi gas confined to two dimensions in an optical lattice. Using radio-frequency spectroscopy we measure the interaction energy of gas. observe confinement-induced Feshbach resonance find existence molecules very good agreement with theoretical predictions.

We demonstrate time-resolved counting of single atoms extracted from a weakly interacting Bose-Einstein condensate 87Rb atoms. The are detected with high-finesse optical cavity and atom transits identified. An laser beam is formed by continuously output coupling the condensate. investigate full statistics this measure its second order correlation function g((2))(tau) in Hanbury Brown-Twiss type experiment. For monoenergetic we observe constant g((2))(tau)=1.00 +/- 0.01 an number distribution...

We have studied mixtures of fermionic (40)K and bosonic (87)Rb quantum gases in a three-dimensional optical lattice. observe that an increasing admixture the species diminishes phase coherence atoms as measured by studying both visibility matter wave interference pattern length bosons. Moreover, we find attractive interactions between bosons fermions lead to increase boson density lattice which measure three-body recombination In our data, do not loss atoms. An analysis thermodynamics...

We create molecules from fermionic atoms in a three-dimensional optical lattice using Feshbach resonance. In the limit of low tunneling, individual wells can be regarded as independent harmonic oscillators. The measured binding energies for varying scattering length agree excellently with theoretical prediction two interacting oscillator. demonstrate that formation used to measure occupancy and perform thermometry.

We investigate the propagation of spin impurity atoms through a strongly interacting one-dimensional Bose gas. The initially well localized impurities are accelerated by constant force, very much analogous to electrons subject bias voltage, and propagate as wave packet. follow motion in situ characterize interaction induced dynamics. observe complex nonequilibrium dynamics, including emergence large density fluctuations remaining gas, multiple scattering events leading dissipation impurity's motion.

We study a spin-polarized degenerate Fermi gas interacting via $p$-wave Feshbach resonance in an optical lattice. The strong confinement available this system allows us to realize one- and two-dimensional gases and, therefore, restrict the asymptotic scattering states of atomic collisions. When aligning spins along (or perpendicular to) axis motion one-dimensional gas, into channels with projection angular momentum $|m|=1$ $m=0$) can be inhibited. In two three dimensions, we observe doublet...

The phase transition of Bose-Einstein condensation is studied in the critical regime, when fluctuations extend far beyond length scale thermal de Broglie waves. Using matter-wave interference we measure correlation these as a function temperature. diverging behavior above temperature observed, from which determine exponent for trapped, weakly interacting Bose gas to be $ν=0.67\pm 0.13$. This measurement has direct implications understanding second order transitions.

We investigate collective excitations of a harmonically trapped two-dimensional Fermi gas from the collisionless (zero sound) to hydrodynamic (first regime. The breathing mode, which is sensitive equation state, observed with an undamped amplitude at frequency 2 times dipole mode for large range interaction strengths and different temperatures. This provides evidence dynamical SO(2,1) scaling symmetry gas. Moreover, we quadrupole measure shear viscosity study its temperature dependence.

We present the realization of a combined trapped-ion and optical cavity system, in which single Yb^+ ion is confined by micron-scale trap inside 230 mum-long fiber cavity. characterize spatial ion-cavity coupling measure strength using cavity-stimulated Lambda-transition. Owing to small mode volume resonator, coherent between photon exceeds natural decay rate dipole moment. This system can be integrated into ion-photon quantum networks step towards quantum-electrodynamics (cavity-QED) based...

A novel combination of hard carbon anode sodium pre‐loading and a tailored electrolyte is used to prepare room temperature sodium‐sulfur full cell batteries. The electrochemical loading with ions realized in specific mixture diethyl carbonate, ethylene fluoroethylene carbonate order create first solid interface (SEI) on the surface. Combining such anodes porous carbon/sulfur composite cathode results cells significantly decreased polysulfide shuttle when compared half combined metallic...

The subtle interplay between kinetic energy, interactions, and dimensionality challenges our comprehension of strongly correlated physics observed, for example, in the solid state. In this quest, Hubbard model has emerged as a conceptually simple, yet rich describing such physics. Here we present an experimental determination equation state repulsive two-dimensional over broad range interactions 0≲U/t≲20 temperatures, down to kBT/t=0.63(2) using high-resolution imaging ultracold fermionic...

X-ray photoelectron spectroscopy (XPS) is a key method for studying (electro-)chemical changes in metal-ion battery electrode materials. In recent publication, we pointed out conflict binding energy (BE) scale referencing at alkali metal samples, which manifested systematic deviations of the BEs up to several eV due specific interaction between highly reactive contact with non-conducting surrounding species. The consequences this phenomenon XPS data interpretation are discussed present...

Abstract Fabry–Perot interferometers have stimulated numerous scientific and technical applications ranging from high-resolution spectroscopy over metrology, optical filters, to interfaces of light matter at the quantum limit more. End facet machining fibers has enabled miniaturization cavities. Integration with fiber wave guide technology allows for small yet open devices favorable scaling properties including mechanical stability compact mode geometry. These cavities (FFPCs) are...