30 research outputs found
Alkaline earth atoms in optical tweezers
We demonstrate single-shot imaging and narrow-line cooling of individual
alkaline earth atoms in optical tweezers; specifically, strontium-88 atoms
trapped in light. We achieve high-fidelity
single-atom-resolved imaging by detecting photons from the broad singlet
transition while cooling on the narrow intercombination line, and extend this
technique to highly uniform two-dimensional arrays of tweezers. Cooling
during imaging is based on a previously unobserved narrow-line Sisyphus
mechanism, which we predict to be applicable in a wide variety of experimental
situations. Further, we demonstrate optically resolved sideband cooling of a
single atom close to the motional ground state of a tweezer. Precise
determination of losses during imaging indicate that the branching ratio from
P to D is more than a factor of two larger than commonly
quoted, a discrepancy also predicted by our ab initio calculations. We also
measure the differential polarizability of the intercombination line in a
tweezer and achieve a magic-trapping configuration by tuning
the tweezer polarization from linear to elliptical. We present calculations, in
agreement with our results, which predict a magic crossing for linear
polarization at and a crossing independent of polarization
at 500.65(50)nm. Our results pave the way for a wide range of novel
experimental avenues based on individually controlled alkaline earth atoms in
tweezers -- from fundamental experiments in atomic physics to quantum
computing, simulation, and metrology implementations
Detection of Bosenovae with Quantum Sensors on Earth and in Space
In a broad class of theories, the accumulation of ultralight dark matter
(ULDM) with particles of mass
leads the to formation of long-lived bound states known as boson stars. When
the ULDM exhibits self-interactions, prodigious bursts of energy carried by
relativistic bosons are released from collapsing boson stars in bosenova
explosions. We extensively explore the potential reach of terrestrial and
space-based experiments for detecting transient signatures of emitted
relativistic bursts of scalar particles, including ULDM coupled to photons,
electrons, and gluons, capturing a wide range of motivated theories. For the
scenario of relaxion ULDM, we demonstrate that upcoming experiments and
technology such as nuclear clocks as well as space-based interferometers will
be able to sensitively probe orders of magnitude in the ULDM coupling-mass
parameter space, challenging to study otherwise, by detecting signatures of
transient bosenova events. Our analysis can be readily extended to different
scenarios of relativistic scalar particle emission.Comment: 16 pages, 9 figure
Optical Telecommunications-Band Clock based on Neutral Titanium Atoms
We propose an optical clock based on narrow, spin-forbidden M1 and E2
transitions in laser-cooled neutral titanium. These transitions exhibit much
smaller black body radiation shifts than those in alkaline earth atoms, small
quadratic Zeeman shifts, and have wavelengths in the S, C, and L-bands of
fiber-optic telecommunication standards, allowing for integration with robust
laser technology. We calculate lifetimes; transition matrix elements; dynamic
scalar, vector, and tensor polarizabilities; and black body radiation shifts of
the clock transitions using a high-precision relativistic hybrid method that
combines a configuration interaction and coupled cluster approaches. We also
calculate the line strengths and branching ratios of the transitions used for
laser cooling. To identify magic trapping wavelengths, we have completed the
largest-to-date direct dynamical polarizability calculations. Finally, we
identify new challenges that arise in precision measurements due to magnetic
dipole-dipole interactions and describe an approach to overcome them. Direct
access to a telecommunications-band atomic frequency standard will aid the
deployment of optical clock networks and clock comparisons over long distances.Comment: 5 pages, 2 figures main text; 8 pages, 3 figures supplementary tex
Alkaline earth atoms in optical tweezers
We demonstrate single-shot imaging and narrow-line cooling of individual alkaline-earth atoms in optical tweezers; specifically, strontium trapped in 515.2−nm light. Our approach enables high-fidelity detection of single atoms by imaging photons from the broad singlet transition while cooling on the narrow intercombination line, and we extend this technique to highly uniform two-dimensional tweezer arrays with 121 sites. Cooling during imaging is based on a previously unobserved narrow-line Sisyphus mechanism, which we predict to be applicable in a wide variety of experimental situations. Further, we demonstrate optically resolved sideband cooling of a single atom to near the motional ground state of a tweezer, which is tuned to a magic-trapping configuration achieved by elliptical polarization. Finally, we present calculations, in agreement with our experimental results, that predict a linear-polarization and polarization-independent magic crossing at 520(2) nm and 500.65(50) nm, respectively. Our results pave the way for a wide range of novel experimental avenues based on individually controlled alkaline-earth atoms in tweezers—from fundamental experiments in atomic physics to quantum computing, simulation, and metrology
Electric dipole moments and the search for new physics
Static electric dipole moments of nondegenerate systems probe mass scales for
physics beyond the Standard Model well beyond those reached directly at high
energy colliders. Discrimination between different physics models, however,
requires complementary searches in atomic-molecular-and-optical, nuclear and
particle physics. In this report, we discuss the current status and prospects
in the near future for a compelling suite of such experiments, along with
developments needed in the encompassing theoretical framework.Comment: Contribution to Snowmass 2021; updated with community edits and
endorsement
Recommended from our members
Cold atoms in space: community workshop summary and proposed road-map
We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies