6 research outputs found
Atom Interferometric Imaging of Differential Potentials Using an Atom Laser
Interferometry is a prime technique for modern precision measurements. Atoms,
unlike light, have significant interactions with electric, magnetic, and
gravitational fields, making their use in interferometric applications
particularly versatile. Here, we demonstrate atom interferometry to image
optical and magnetic potential landscapes over an area exceeding . The differential potentials employed in our experiments
generate phase imprints in an atom laser that are made visible through a Ramsey
pulse sequence. We further demonstrate how advanced pulse sequences can enhance
desired imaging features, e.g. to image steep potential gradients. A
theoretical discussion is presented that provides a semiclassical analysis and
matching numerics.Comment: Updated to match published version. 13 pages, 9 figure
Quantum Gas Mixtures and Dual-Species Atom Interferometry in Space
The capability to reach ultracold atomic temperatures in compact instruments
has recently been extended into space. Ultracold temperatures amplify quantum
effects, while free-fall allows further cooling and longer interactions time
with gravity - the final force without a quantum description. On Earth, these
devices have produced macroscopic quantum phenomena such as Bose-Einstein
condensation (BECs), superfluidity, and strongly interacting quantum gases.
Quantum sensors interfering the superposition of two ultracold atomic isotopes
have tested the Universality of Free Fall (UFF), a core tenet of Einstein's
classical gravitational theory, at the level. In space, cooling the
elements needed to explore the rich physics of strong interactions and
preparing the multiple species required for quantum tests of the UFF has
remained elusive. Here, utilizing upgraded capabilities of the multi-user Cold
Atom Lab (CAL) instrument within the International Space Station (ISS), we
report the first simultaneous production of a dual species Bose-Einstein
condensate in space (formed from Rb and K), observation of
interspecies interactions, as well as the production of K ultracold
gases. We have further achieved the first space-borne demonstration of
simultaneous atom interferometry with two atomic species (Rb and
K). These results are an important step towards quantum tests of UFF in
space, and will allow scientists to investigate aspects of few-body physics,
quantum chemistry, and fundamental physics in novel regimes without the
perturbing asymmetry of gravity
Catastrophe Atom Optics: Fold and Cusp Caustics in an Atom Laser
Typically discussed in the context of optics, caustics are envelopes of
classical trajectories (rays) where the density of states diverges, resulting
in pronounced observable features such as bright points, curves, and extended
networks of patterns. Here, we generate caustics in the matter waves of an atom
laser, providing a striking experimental example of catastrophe theory applied
to atom optics in an accelerated (gravitational) reference frame. We showcase
caustics formed by individual attractive and repulsive potentials, and present
an example of a network generated by multiple potentials. Exploiting internal
atomic states, we demonstrate fluid-flow tracing as another tool of this
flexible experimental platform. The effective gravity experienced by the atoms
can be tuned with magnetic gradients, forming caustics analogous to those
produced by gravitational lensing. From a more applied point of view, atom
optics affords perspectives for metrology, atom interferometry, and
nanofabrication. Caustics in this context may lead to quantum innovations as
they are an inherently robust way of manipulating matter waves.Comment: 10 pages, 6 figure
Experimental realization of a non-magnetic one-way spin switch
Controlling magnetism through non-magnetic means is highly desirable for future electronic devices, as such means typically have ultra-low power requirements and can provide coherent control. In recent years, great experimental progress has been made in the field of electrical manipulation of magnetism in numerous material systems. These studies generally do not consider the directionality of the applied non-magnetic potentials and/or magnetism switching. Here, we theoretically conceive and experimentally demonstrate a non-magnetic one-way spin switch device using a spin-orbit coupled Bose–Einstein condensate subjected to a moving spin-independent repulsive dipole potential. The physical foundation of this unidirectional device is based on the breakdown of Galilean invariance in the presence of spin-orbit coupling. Such a one-way spin switch opens an avenue for designing quantum devices with unique functionalities and may facilitate further experimental investigations of other one-way spintronic and atomtronic devices.
For use in electronic and quantum applications, controlling the magnetism of a system through non-magnetic means is important. Here, the authors demonstrate a unidirectional non-magnetic spin-switch device using spin-momentum coupling in Bose–Einstein condensates of ultracold Rb-87 atoms