Session M02: Student Oral Presentations II

SACNAS: Diversity in Physics and STEM

Physics is a difficult field of study. Furthermore the challenges underrepresented minorities (URM) face during their academic careers significantly contribute to the deficit of URM in STEM positions. URMs also tend to be first generation students which means they lack collegial guidance from their families. From financial issues to lack of educational and professional development, URMs face obstacles that can be remedied by organizations dedicated to tackling these challenges.~ The Society for the Advancement of Chicanos/Hispanics and Native Americans in Science (SACNAS) is an organization founded to address these obstacles. We will discuss the efforts made by the SACNAS chapter at the University of Houston to support URMs in STEM fields through mentorship, community engagement, and online gatherings before and during the COVID-19 pandemic. These events have been in the form of resume/CV workshops, NSF GRFP review sessions, and online gaming events. Moreover, we will discuss the merits of facilitating an environment of diversity and inclusivity of not just race/ethnicity but of scientific backgrounds as well. Such environments allow for the development of science communication skills when physicists interact with individuals outside of their respective fields.   

An Unstable Equilibrium: My Journey in Physics as a DACA Recipient

According to the US Department of Homeland Security there are 643,430 immigrants protected under the Deferred Action for Childhood Arrival (DACA) program as of March 2020. DACA has allowed these young immigrants to continue living in the US, and pursue their careers. On a more personal note, this program provides a critical amnesty for me to continue with my doctoral studies. However, my opportunities in physics have been limited due to my status. Federal grants, traveling abroad to work, and internships at national labs are out of reach for all DACA students. I often found myself overwhelmed by the uncertain future of DACA during the prior administration. Nonetheless, these downsides and worries pale in comparison to how empowering this program has been. I hope that by sharing my experiences in looking for research experience as an undergrad, applying to grad schools, and searching for grants will shed some light on how impactful DACA has been.   

Transition Metal Doped ZnS Quantum Dots for Photovoltaic Applications

Traditional semiconductors can be doped with magnetic transition metal elements to create the diluted magnetic semiconductors; their properties change depending on the dopants. In some cases, this is corresponding to an enhancement in the photo-to-current efficiency of doped quantum dots in the sensitized solar cells. Here, we observed the optical and transport properties of the transition metals doped with Zinc Sulfide quantum dots and optimized them for better photovoltaics. Additionally, we explored how the different dopants lead to changes in the bandgap and distinguished the characteristic of the eight diluted magnetic semiconductors. By further analyzing the absorption data, Cobalt-Nickel doped ZnS was found to have the highest absorbance in the visible range out of all the single and co-doped, as well as tri-doped quantum dots which made it the best candidate for optoelectronic device fabrication.   

The Influence of Wind and Buoyancy Forcing on Antarctic Bottom Water Export

Ocean circulation plays a key role in the climate system globally. Antarctic bottom water (AABW), the densest water mass, blankets much of the ocean bottom in the southern hemisphere. Formation and export of AABW comprises the deepest limb of the global circulation. Export of AABW in the Southern Ocean is either forced by wind by exchanges of heat and freshwater with the atmosphere. We know that both wind and heat/freshwater forcing are important in setting the mean state of the Southern Ocean overturning circulation and what is poorly understood is their contributions to time-variability of the Southern Ocean overturning circulation. To investigate overturning circulation, we developed a theory that describes the adjustment of AABW export to changes in wind and heat/freshwater forcing and we will be comparing the predictions of this theory with process-oriented simulations of an idealized AABW export subject to time-varying forcing. Currently, a simplified version is being investigated, describing the depth-averaged response in the Southern Ocean. Next, the simulation will be extended to include depth-dependence effects, to account for the overturning circulation response. We will use the theory and simulations to test the hypothesis that wind modifies AABW export on short time scales (up to several years) and that heat/freshwater fluxes do so on longer time scales. These results will inform future observations and predictions of overturning circulation in the Southern Ocean.   

Space is the medium of radiation particle movement

pace is the medium for the movement of radiation particles. Only the speed at which the medium changes radiation can the medium have quality. There are two forms of media: 1. Vacuum, absolutely still, and without mass. Radiation particles move at the speed of light, and there is no mass in vacuum space. 2. Non-vacuum, relative movement, and mass. The non-vacuum range is very wide. The microscopic appearance is: atomic nuclei, electrons, quarks and even more basic particles, the macroscopic appearance is: satellites, planets, stars, galaxies, black holes and even dark matter and other celestial bodies. Obviously there is mass in non-vacuum space. Non-vacuum space slows down the speed of radiation particles, thus forming mass. Dark matter (this special medium) can stop any radiation particles from moving, so the mass of dark matter is extremely huge, and the mass of dark matter is extremely huge