3,151 research outputs found
An Atom Faucet
We have constructed and modeled a simple and efficient source of slow atoms.
From a background vapour loaded magneto-optical trap, a thin laser beam
extracts a continuous jet of cold rubidium atoms. In this setup, the extraction
column that is typical to leaking MOT systems is created without any optical
parts placed inside the vacuum chamber. For detailed analysis, we present a
simple 3D numerical simulation of the atomic motion in the presence of multiple
saturating laser fields combined with an inhomogeneous magnetic field. At a
pressure of mbar, the moderate laser power of
10 mW per beam generates a jet of flux atoms/s with a
mean velocity of 14 m/s and a divergence of mrad.Comment: Submitted to EPJD. 1 TeX file (EPJ format), 7 picture
Covid-19\u27s Effect on Education
The purpose for this paper is to inform the reader of what the effect of the Covid-19 pandemic has on students and teachers along with finding solutions. The biggest concern during this time is if students are meeting the required materials while in school. Many students are falling behind and there needs to be a solution on how to solve this problem. Covid has caused many problems in everyone’s life but, especially in the lives of students. Teachers are struggling to find solutions due to limitations of Nontraditional Instruction and virtual classrooms. Parents and teachers can team up to help one another out and to achieve the goals of their student(s)
Vortex formation in a stirred Bose-Einstein condensate
Using a focused laser beam we stir a Bose-Einstein condensate of 87Rb
confined in a magnetic trap and observe the formation of a vortex for a
stirring frequency exceeding a critical value. At larger rotation frequencies
we produce states of the condensate for which up to four vortices are
simultaneously present. We have also measured the lifetime of the single vortex
state after turning off the stirring laser beam.Comment: 4 pages, 3 figure
Bose-Einstein Condensates with Large Number of Vortices
We show that as the number of vortices in a three dimensional Bose-Einstein
Condensate increases, the system reaches a "quantum Hall" regime where the
density profile is a Gaussian in the xy-plane and an inverted parabolic profile
along z. The angular momentum of the system increases as the vortex lattice
shrinks. However, Coriolis force prevents the unit cell of the vortex lattice
from shrinking beyond a minimum size. Although the recent MIT experiment is not
exactly in the quantum Hall regime, it is close enough for the present results
to be used as a guide. The quantum Hall regime can be easily reached by
moderate changes of the current experimental parameters.Comment: 4 pages, no figure
Feshbach resonances in ultracold 85Rb-87Rb and 6Li-87Rb mixtures
We present an analysis of experimentally accessible magnetic Feshbach
resonances in ultra-cold hetero-nuclear 85Rb-87Rb and 6Li-87Rb mixtures. Using
recent experimental measurements of the triplet scattering lengths for 6Li-87Rb
and 7Li-87Rb mixtures and Feshbach resonances for one combination of atomic
states, we create model potential curves and fine tune them to reproduce the
measured resonances and to predict the location of several experimentally
relevant resonances in Li-Rb collisions. To model 85Rb-87Rb collisions, we use
accurate Rb_2 potentials obtained previously from the analysis of experiments
on 87Rb-87Rb collisions. We find resonances that occur at very low magnetic
fields, below 10 G, which may be useful for entanglement generation in optical
lattices or atom chip magnetic traps.Comment: 8 pages, 5 figure
Caught Between Land and Sea: West End as a Maritime Lake Community on Lake Pontchartrain
West End has eluded traditional New Orleans history as academics have continued to view the city\u27s history and maritime culture through the Mississippi River. This project looks at the development of West End using the Sintes family and its boatbuilding business as a case study on how generational businesses are affected by tourism, natural disasters, and urban development. This project has used oral histories of the Sintes family to tell their personal story of West End, this terraqueous gap filled with boats, crawfish boils, natural disasters, and human loss, and in doing so, preserved and recorded a part of West End\u27s maritime lake culture that might otherwise be lost
Caught Between Land and Sea: West End as a Maritime Lake Community on Lake Pontchartrain
West End has eluded traditional New Orleans history as academics have continued to view the city\u27s history and maritime culture through the Mississippi River. This project looks at the development of West End using the Sintes family and its boatbuilding business as a case study on how generational businesses are affected by tourism, natural disasters, and urban development. This project has used oral histories of the Sintes family to tell their personal story of West End, this terraqueous gap filled with boats, crawfish boils, natural disasters, and human loss, and in doing so, preserved and recorded a part of West End\u27s maritime lake culture that might otherwise be lost
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