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Projects
Optical Dipole Trap
Carlos Alvarado - Contra Costa College
Mentor: Dr. Arne Schwettmann
Optical dipole trapping differs from radiation force trapping by minimizing optical excitations and associated recoil
through far-detuned light from the atomic resonance. The optical dipole force, arising from the interaction between
an atom's induced dipole moment and the light field's gradient. The resulting dipole potential, influenced by laser intensity
and detuning, creates regions of varying intensity in focused laser beams. Red-detuned beams attract atoms toward high-intensity regions, w
hile blue-detuned beams repel them. My job of balancing intensity, detuning, and trap configurations is crucial,
as higher intensity and smaller detuning provide tighter confinement but increase the scattering rate. Optimal trapping
combines large detuning and high intensity to achieve strong confinement with minimal scattering effects.
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Stellar Evolution as a Probe for Light Dark Matter Particles
Kaleb Anderson - Brown University
Mentor: Dr. Kuver Sinha
After decades of using arguments from naturalness to guide our searches for elusive dark matter particles, results from the LHC
at CERN have continued to restrict the phase space of supersymmetric partners. Consequently, it may be time to employ more of a
ground-up approach to the search for dark matter, where we determine what generic model-independent predictions may be made within
a given mass range. We intend to implement this methodology in the search for light dark matter particles within the axion-like
particle mass range by determining some of the effects of such hypothetical particles on stellar evolution and, consequently,
on stellar populations.
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The CIA Mystery: Collision-Induced Absorption in Ultracool White Dwarfs
Madison Bernice - Louisiana Tech University
Mentor: Dr. Mukremin Kilic
Ultracool white dwarfs are conceivably the coolest and oldest white dwarfs in our Galaxy, and therefore are of paramount importance
for white dwarf cosmochronology. In the infrared, ultracool white dwarfs exhibit irregular spectral energy distributions with compelling
collision-induced absorption features. Because current atmosphere models fail to accurately describe spectral energy distributions
of ultracool white dwarfs, the very nature of these objects is still in question. Discrepancies between the temperatures and masses
of ultracool white dwarfs insinuates a multi-billion-year disagreement on their presumed cooling ages. The main distinction between
these disunited analyses is the choice of collision-induced absorption opacities. By obtaining and utilizing infrared spectroscopy
of ultracool white dwarfs, we can unveil collision-induced absorption features and ultimately resolve the debate on the nature
of ultracool white dwarfs.
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The Higgs Boson and the Search for Charm Quark Decay Modes
Mrinal Bhatnagar - Wesleyan University
Mentor: Dr. Chung Kao
In this talk, I will give an overview of the Higgs boson and why it is required to give mass to the
weak gauge bosons, which will include an overview of gauge theory. I will then introduce the goal of
simulating decay modes for the Higgs boson with an emphasis on the production of charm quarks.
Finally, I will introduce the Monte Carlo method, a technique I will be using in my research this summer.
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Angular Momentum of Stars During Formation: Effect of Accretion History on Star-Disk Interactions
Jenna Brustad - Trinity College
Mentor: Dr. Sean Matt
During a star's formation, specifically the accretion phase, the interaction between stars and their surrounding accretion disks can significantly impact the star's
angular momentum. Many previous models of angular momentum evolution in low-mass stars during the accretion phase have assumed a constant rotation rate. However,
numerous external factors, including their accretion history, can influence spin rates during this phase. This summer, in my research, I will be modeling the spin rates
of stars during the accretion phase using a spin evolution code known as dizzyStars. I will consider the effects that star-disk interactions can have on spin rates
during this phase and compare the results to observational data. These models will also use updated Torque prescriptions and also explore the effects of different accretion histories.
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Saturated Absorption Spectroscopy of 87Rb: Towards Achieving Bose-Einstein Condensates
Jessica Clark - Washington and Lee University
Mentor: Dr. Emine Altuntas
Bose-Einstein Condensate (BEC) is a quantum-statistical phase transition that exhibits
quantum phenomena at a macroscopic level. We use 87Rb atoms for generating our BECs.
Since a BEC consists of bosons in the ground state, one must cool the atoms to extremely low
temperatures (~170 nK), where laser cooling is the ubiquitous technique. Towards this, we
employ the Doppler-free saturated absorption spectroscopy to lock our laser to the correct
frequency for the D2 transition in 87Rb. This is a process
that uses two counter-propagating lasers, which I will describe in this talk.
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TBD
Lydia England - University of Oklahoma
Mentor: Dr. Bruno Uchoa
Historically, material properties are studied through electronic band structures of solids. However,
the rich geometric structure of the Hilbert space of eigenstates is itself responsible for certain properties
of crystalline materials. We examine the quantum geometric tensor (QGT) which encodes completely
the geometric properties of quantum states, in particular reviewing the Berry curvature — the imaginary part of the QGT —
and its relationship to the Berry connection and Berry phase. We also consider the real part of the QGT,
called the "quantum metric," and discuss our future plans to calculate its effects on material properties.
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Growth and Characterization of Ultra-Thin Crystalline Organic Thin Films for Optoelectronic Applications
Samuel Fulbright - Drury University
Mentor: Drs. Lloyd Bumm and Madalina Furis
The search for next-generation organic semiconductors for optoelectronic
applications is important because they have the potential to replace the usage of
traditional semiconductors like silicon in electronics while also providing additional
benefits such as a much lower material cost, more flexibility, lightness, and
biodegradability. Both the groups I am working with are characterizing a relatively
new molecular material from a family of alkoxy-substituted quadrupolar fluorescent
dyes. With the Furis group, I will be helping with the deposition of organic thin films
on substrates and aiding in subsequent optical and structural characterization. With
the Bumm group, I will be using various microscopy methods including atomic force
microscopy and polarized microscopy to view the physical and electrical properties of
the crystalline thin films in order to establish the influence of long-range ordering on
optoelectronic properties.
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Zero-range Interacting Atoms in Low-dimensional Harmonic Traps
Jacob Norris - University of Oklahoma
Mentor: Dr. Doerte Blume
Magneto-optical traps are a powerful technique in experimental atomic physics, allowing for the cooling of atoms down
to the microkelvin regime. At such cold temperatures, two- and three-particle systems have been successfully modeled
using zero-range interactions. We review results for two particles in a one-dimensional harmonic trap with either even
or odd parity scattering and discuss our plans to generalize the theoretical treatment to three-
and four-particle systems with bosonic, fermionic, or mixed exchange statistics.
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Gamma Ray Properties of NLS1s
Rana Osman - University of Colorado Boulder
Mentor: Dr. Emilia Järvelä
Narrow line Seyfert 1 (NLS1) galaxies are a type of AGN characterized by their lower supermassive black hole masses
and high Eddington ratios. The previously accepted model of AGNs reflected that AGNs with higher supermassive black hole masses,
lower Eddington ratios, with massive early-stage host galaxies, and high radio loudness are highly favored in their capability
of launching powerful relativistic jets. Observations of NLS1s, which do not fit this paradigm, hosting jets contributed
to the breaking of this metric. Detecting gamma rays from NLS1s provides a decent stand in metric as they can typically only
be detected when jetting occurs. Several more NLS1 jets have been detected since the first but a recent cleaning
of the largest sample of NLS1s to date gives us the opportunity to attempt a more holistic study of about 4000 NLS1s.
This summer I hope to get through at least the first 7 sources, selected because of their extreme radio variablility.
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Metallicity in Low Mass Stars and How it effects their Stellar Rotation
Jordan Riley - University of Oklahoma
Mentor: Dr. Sean Matt
The metallicity in low mass stars is important in understanding how those stars spin down and evolve over time. Metallicity wasn't a
highly researched topic in stellar astrophysics until recently. Most studies have assumed solar metallicity within their models. With
recent studies, we learned that the chemical composition of a star does influence how well the star spins down over time. Using data
from the Praesepe cluster, we compare it with model data to find the best fit plots for metallicity at certain ages. The reason we are
using the Praesepe cluster is because it is a young open cluster with a wide range of masses, rotation periods, and all the stars have
the same chemical composition. With these new models, we will be able to compare other sets of data to determine metallicity of stars
and their spin evolution.
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Exploring adiabatic short-cut protocols in two-state systems with dissipation
Madie van Staveren - University of Oklahoma
Mentor: Dr. Doerte Blume
Adiabatic short-cut protocols allow one to prepare target quantum states faster than
expected based on slow, adiabatic changes of the system Hamiltonian. Recently,
adiabatic short-cut protocols have been applied in the context of open quantum systems
described by master equations. My REU project aims at exploring such protocols for a
two-level system. To get started, I developed a program in python to solve the
differential equations for the expansion coefficients of a two-state wave function. The
numerical solution was found using the fourth-order Runge Kutta method and validated
by comparing with analytical solutions. My goal now is to generalize the program and
apply it to density matrices to solve the Lindblad master equation.
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