206 research outputs found
Quantum magnetism with ultracold molecules
This article gives an introduction to the realization of effective quantum
magnetism with ultracold molecules in an optical lattice, reviews experimental
and theoretical progress, and highlights future opportunities opened up by
ongoing experiments. Ultracold molecules offer capabilities that are otherwise
difficult or impossible to achieve in other effective spin systems, such as
long-ranged spin-spin interactions with controllable degrees of spatial and
spin anisotropy and favorable energy scales. Realizing quantum magnetism with
ultracold molecules provides access to rich many-body behaviors, including many
exotic phases of matter and interesting excitations and dynamics.
Far-from-equilibrium dynamics plays a key role in our exposition, just as it
did in recent ultracold molecule experiments realizing effective quantum
magnetism. In particular, we show that dynamical probes allow the observation
of correlated many-body spin physics, even in polar molecule gases that are not
quantum degenerate. After describing how quantum magnetism arises in ultracold
molecules and discussing recent observations of quantum magnetism with polar
molecules, we survey prospects for the future, ranging from immediate goals to
long-term visions.Comment: 21 pages, 6 figures, 1 table. Review articl
Stirring trapped atoms into fractional quantum Hall puddles
We theoretically explore the generation of few-body analogs of fractional
quantum Hall states. We consider an array of identical few-atom clusters
(n=2,3,4), each cluster trapped at the node of an optical lattice. By
temporally varying the amplitude and phase of the trapping lasers, one can
introduce a rotating deformation at each site. We analyze protocols for
coherently transferring ground state clusters into highly correlated states,
producing theoretical fidelities in excess of 99%.Comment: 4 pages, 3 figures (13 subfigures) -- v2: published versio
High temperature thermodynamics of fermionic alkaline earth atoms in optical lattices
We calculate experimentally relevant properties of trapped fermionic alkaline
earth atoms in an optical lattice, modeled by the SU(N) Hubbard model. Our
calculation is accurate when the temperature is much larger than the tunneling
rate, similar to current regimes in ultracold atom experiments. In addition to
exploring the Mott insulator-metal crossover, we calculate final temperatures
achieved by the standard experimental protocol of adiabatically ramping from a
non-interacting gas, as a function of initial gas temperature and final state
lattice parameters. Of particular experimental interest, we find that
increasing gives substantially \textit{colder} Mott insulators, up to more
than a factor of five for relevant parameters. This cooling happens for all
, fixing the initial entropy, or for all N \lsim 20 (the exact value
depends on dimensionality), fixing the initial temperature.Comment: 4+ pages main text, 2 figures. 3 pages supplementary information, 2
figures. v2: added citatio
A Novel Dielectric Anomaly in Cuprates and Nickelates: Signature of an Electronic Glassy State
The low-frequency dielectric response of hole-doped insulators
La_{2}Cu_{1-x}Li_{x}O_{4} and La_{2-x}Sr_{x}NiO_{4} shows a large dielectric
constant \epsilon ^{'} at high temperature and a step-like drop by a factor of
100 at a material-dependent low temperature T_{f}. T_{f} increases with
frequency and the dielectric response shows universal scaling in a Cole-Cole
plot, suggesting that a charge glass state is realized both in the cuprates and
in the nickelates.Comment: 5 pages, 4 figure
Disparities in eating disorder risk and diagnosis among sexual minority college students: Findings from the national Healthy Minds Study
ObjectiveTo examine differences in eating disorder (ED) risk and diagnosis by sexual orientation in a national sample of college students.MethodData from 178 U.S. colleges and universities participating in the Healthy Minds Study between 2016 and 2019 were analyzed (36,691 cisgender men, 81,730 cisgender women; 15.7% self‐identifying as sexual minorities). Outcomes were ED risk (≥2 on the SCOFF) and self‐reported lifetime ED diagnosis. Prevalence estimates adjusted for demographics and weight status were computed via logistic regression.ResultsHigher proportions of questioning (29.1%), bisexual (26.3%), and gay men (30.9%) exhibited elevated risk than heterosexual men (14.3%), and a higher proportion of gay men exhibited elevated risk than bisexual men. Higher proportions of questioning (34.5%) and bisexual women (34.6%) exhibited elevated risk than heterosexual women (27.6%); proportions of lesbian (28.1%) and heterosexual women were similar. Among those with elevated risk, higher proportions of bisexual (5.0%) and gay men (7.1%) and of questioning (14.7%), bisexual (18.1%), and lesbian women (19.6%) had been diagnosed relative to heterosexual men (2.0%) and heterosexual women (10.3%), respectively.DiscussionQuestioning and bisexual individuals appear to be particularly vulnerable; they may experience elevated ED risk relative to their heterosexual peers yet underdiagnosis relative to their gay or lesbian peers.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162796/2/eat23304_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162796/1/eat23304.pd
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