Versatile transporter apparatus for experiments with optically trapped Bose–Einstein condensates

Abstract

Abstract. We describe a versatile and simple scheme for producing magnetically and optically-trapped 87 Rb Bose-Einstein condensates, based on a moving-coil transporter apparatus. The apparatus features a TOP trap that incorporates the movable quadrupole coils used for magneto-optical trapping and long-distance magnetic transport of atomic clouds. As a stand-alone device, this trap allows for the stable production of condensates containing up to one million atoms. In combination with an optical dipole trap, the TOP trap acts as a funnel for efficient loading, after which the quadrupole coils can be retracted, thereby maximizing optical access. The robustness of this scheme is illustrated by realizing the superfluid-to-Mott insulator transition in a three-dimensional optical lattice.

Spontaneous emission of matter waves from a tunable open quantum system

“…Starting with an optically-trapped Bose-Einstein condensate [28], we first adiabatically irreversible, exponential decay in agreement with the expectation; however, the measured population does not decay to zero but instead saturates at a finite value. This discrepancy is readily explained if one takes into account that an excited emitter is not isolated but part of a (mostly) ground-state array that enables reabsorption, in analogy to an optically thick medium.…”

Superfluid Bloch dynamics in an incommensurate optical lattice

“…In our experiment we load a BEC of a few 10 4 87 Rb atoms in the ≡ − F m , 2, 2 F hyperfine state into a crossed optical dipole trap (XODT) [44]. A magnetic field gradient levitates the BEC in the trap, before a one-dimensional biochromatic optical lattice potential is used as a measure of the lattice commensurability; for nearly irrational β, the lattices will be periodic on length scales exceeding those relevant to the experiment, thus realizing an effectively incommensurate quasidisordered potential.…”

Superfluidity of Interacting Bosonic Mixtures in Optical Lattices

“…These mixtures are subsequently loaded into an adiabatically ramped up 3D optical lattice. The state-independent transverse lattice potentials along x and y are generated by partial retroreflection of the ODT beams [17], maintaining constant gravitational sag through coordination of the forward beam intensities with the amount of retroreflection. The statedependent lattice along z is generated by full retroreflection of a beam at λ z = 785.1 nm (1/e 2 radius: 230 µm).…”