72 research outputs found
Dynamical Realization of Macroscopic Superposition States of Cold Bosons in a Tilted Double Well
We present exact expressions for the quantum sloshing of Bose-Einstein
condensates in a tilted two-well potential. Tunneling is suppressed by a small
potential difference between wells, or tilt. However, tunneling resonances
occur for critical values of the tilt when the barrier is high. At resonance,
tunneling times on the order of 10-100 ms are possible. Furthermore, such
tilted resonances lead to a dynamical scheme for creating few-body NOON-like
macroscopic superposition states which are protected by the many body
wavefunction against potential fluctuations.Comment: 6 pages, 5 figures, final version, only minor changes from previous
arXiv versio
Instructor perspectives on iteration during upper-division optics lab activities
Although developing proficiency with modeling is a nationally endorsed
learning outcome for upper-division undergraduate physics lab courses, no
corresponding research-based assessments exist. Our longterm goal is to develop
assessments of students' modeling ability that are relevant across multiple
upper-division lab contexts. To this end, we interviewed 19 instructors from 16
institutions about optics lab activities that incorporate photodiodes.
Interviews focused on how those activities were designed to engage students in
some aspects of modeling. We find that, according to many interviewees,
iteration is an important aspect of modeling. In addition, interviewees
described four distinct types of iteration: revising apparatuses, revising
models, revising data-taking procedures, and repeating data collection using
existing apparatuses and procedures. We provide examples of each type of
iteration, and discuss implications for the development of future modeling
assessments.Comment: 4 pages, 1 figure; under revie
Access to undergraduate research experiences at a large research university
The American Physical Society recently released a statement calling on all
university physics departments to provide or facilitate access to research
experiences for all undergraduate students. In response, we investigated the
current status of access to undergraduate research at University of Colorado
Boulder (CU), a large research institution where the number of undergraduate
physics majors outnumber faculty by roughly ten to one. We created and
administered two surveys within CU's Physics Department: one probed
undergraduate students' familiarity with, and participation in, research; the
other probed faculty members' experiences as research mentors to
undergraduates. We describe the development of these instruments, our results,
and our corresponding evidence-based recommendations for improving local access
to undergraduate research experiences. Reflecting on our work, we make several
connections to an institutional change framework and note how other
universities and colleges might adapt our process.Comment: 4 pages, 3 figures, 1 table; Submitted to 2015 PERC Proceeding
Student ownership of projects in an upper-division optics laboratory course: A multiple case study of successful experiences
We investigate students' sense of ownership of multiweek final projects in an
upper-division optics lab course. Using a multiple case study approach, we
describe three student projects in detail. Within-case analyses focused on
identifying key issues in each project, and constructing chronological
descriptions of those events. Cross-case analysis focused on identifying
emergent themes with respect to five dimensions of project ownership: student
agency, instructor mentorship, peer collaboration, interest and value, and
affective responses. Our within- and cross-case analyses yielded three major
findings. First, coupling division of labor with collective brainstorming can
help balance student agency, instructor mentorship, and peer collaboration.
Second, students' interest in the project and perceptions of its value can
increase over time; initial student interest in the project topic is not a
necessary condition for student ownership of the project. Third, student
ownership is characterized by a wide range of emotions that fluctuate as
students alternate between extended periods of struggle and moments of success
while working on their projects. These findings not only extend the literature
on student ownership into a new educational domain---namely, upper-division
physics labs---they also have concrete implications for the design of
experimental physics projects in courses for which student ownership is a
desired learning outcome. We describe the course and projects in sufficient
detail that others can adapt our results to their particular contexts.Comment: 22 pages, 3 tables, submitted to Phys. Rev. PE
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