218 research outputs found
Synthetic dimensions in ultracold molecules: quantum strings and membranes
Synthetic dimensions alter one of the most fundamental properties in nature,
the dimension of space. They allow, for example, a real three-dimensional
system to act as effectively four-dimensional. Driven by such possibilities,
synthetic dimensions have been engineered in ongoing experiments with ultracold
matter. We show that rotational states of ultracold molecules can be used as
synthetic dimensions extending to many - potentially hundreds of - synthetic
lattice sites. Microwaves coupling rotational states drive fully controllable
synthetic inter-site tunnelings, enabling, for example, topological band
structures. Interactions leads to even richer behavior: when molecules are
frozen in a real space lattice with uniform synthetic tunnelings, dipole
interactions cause the molecules to aggregate to a narrow strip in the
synthetic direction beyond a critical interaction strength, resulting in a
quantum string or a membrane, with an emergent condensate that lives on this
string or membrane. All these phases can be detected using measurements of
rotational state populations.Comment: 5-page article + 4 figures + references; 7 pages + 4 figures in
Supplemen
Unveiling the Online-Offline Divide: Predicting Retail Channel Membership for Luxury Jewelry Consumers Using Discriminant Analysis
The study explores the factors that influence consumers to choose between online and offline channels for purchasing products and services. Using a quantitative approach, data was collected from 352 respondents through a survey and analyzed using discriminant analysis. The study found that consumers tend to purchase products online for self- gratification, better offers, relative price, variety of products, product information, and better price comparison. On the other hand, consumers choose offline channels for quality, reliable information, quality of judgment, and better after-sales services. The papers implications extend to marketing practitioners, specifically in luxury product marketing for segmentation, targeting, and positioning
Motional decoherence in ultracold Rydberg atom quantum simulators of spin models
Ultracold Rydberg atom arrays are an emerging platform for quantum simulation
and computing. However, decoherence in these systems remains incompletely
understood. Recent experiments [Guardado-Sanchez et al. Phys. Rev. X 8, 021069
(2018)] observed strong decoherence in the quench and longitudinal-field-sweep
dynamics of two-dimensional Ising models realized with Lithium-6 Rydberg atoms
in optical lattices. This decoherence was conjectured to arise from spin-motion
coupling. Here we show that spin-motion coupling indeed leads to decoherence in
qualitative, and often quantitative, agreement with the experimental data,
treating the difficult spin-motion coupled problem using the discrete truncated
Wigner approximation method. We also show that this decoherence will be an
important factor to account for in future experiments with Rydberg atoms in
optical lattices and microtrap arrays, and discuss methods to mitigate the
effect of motion, such as using heavier atoms or deeper traps
Optimization of medium for the production of subtilisin from Bacillus subtilis MTCC 441
Subtilisins (E.C.3.4.21.62) are alkaline proteases that are secreted by members of the genus Bacillus. They are serine proteases that exhibit high specific activity on proteinaceous substrates, function optimally at moderate temperatures, and are stable under alkaline conditions. Thus the use of subtilisin as an enzyme additive could help in development of quality laundry detergents. In this work the subtilisin production from Bacillus subtilis (MTCC 441) was improved by altering and optimizing the media components. This alteration was brought up by process development strategy. The effect of yeast extract, casein, peptone and sodium chloride on subtilisin production was studied and were optimized using Box Behnken Design. The optimal growth conditions for B. subtilis MTCC 441 were found to 37oC, and pH 7.5. The optimal media composition for subtilisin production was found to beyeast extract at 6.75 g/L, peptone at 4.41 g/L, sodium chloride at 6.08 g/L, casein at 10.75 g/L with glucose at 5 g/L. The predicted and observed response were 181.00 U/mg (with desirability =0.87) and 185.70 U/mg, respectively
Tetrakis(1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidin-9-ido-κ2 N 1,N 9)niobium(V) hexafluoridophosphate
The title complex, [Nb(C7H12N3)4]PF6, features chelating hpp anions (hpp is 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine) that define a distorted dodecahedral coordination geometry based on an N8 donor set. The Nb atom is situated on a site of symmetry , and the PF6
− anion has crystallographic fourfold symmetry
- …