Colloquium Archive

Thursday, September 15th
Welcome Back Picnic & Introduction to the Department
Presented by the Physics & Astronomy Department faculty

Learn about being a Physics major. Get to know everyone in the department. Ask questions. EAT!

Noon
Tome Outdoor Classroom
(Rain Location: Tome 2nd floor lounge by Physics faculty offices)
Lunch provided

Thursday, September 22nd
Michael Loalbo '23 will present "The Synthesis and Characterization of Ce2Ti207"

We investigated the synthesis, characterization, thermal expansion, and electrical properties of the rare earth titanium oxide Ce2Ti2O7.  Growth was performed using the optical float zone technique in both nitrogen and air atmosphere.  Powder x-ray diffraction was used to determine the crystallographic space group and lattice parameters.  Through Laue x-ray diffraction, we then oriented the single crystal along the a, b, and c crystallographic directions for directional measurements.

and

Terry Mercer '23 will present "Characterizing the strain-dependence of Raman scattering in 2D Mo0.5W0.5S2"

We constructed an apparatus that can place multiple types of tunable homogenous uniaxial tensile strain upon a polydimethylsiloxane (PDMS) substrate with an exfoliated atomically thin layer of Mo0.5W0.5S2. The percentage of this tunable strain can be computed using python software constructed based upon the multiple derived strain equations; this allows us to know the displacement that needs to place upon the substrate to obtain a specific strain percentage. With this strain device, we were able to characterize these different percentages of strain with the use of Raman spectroscopy and photoluminescence measurements. We found that with increasing both types of strain there is an observed decrease in intensity of the reemitted light as well as a red shift when compared to the zero strain measurements. Then due to the versatility of this apparatus, it can be used for various other types of strain on differing substrates and materials in future projects.

Noon
Tome 115
Pizza provided

Thursday, October 13th
Dr. Todd B. Pittman, UMBC Physics Department
"Single-photon qubits and quantum entanglement"

In recent years there has been an explosion of interest in quantum information processing (QIP), with applications ranging from quantum communications to full-scale quantum computing.  In this talk he will review an optical approach to QIP, where single-photons are used to represent the quantum bits (or “qubits”) of information, and entanglement between distant photons leads to a variety of fascinating and counterintuitive effects. He will highlight his group’s recent experimental work with single and entangled photons, as well as new directions enabled by the ability to accurately detect the absence of photons.

Research group website: quantuminfo.umbc.edu

Noon
Tome 115
Pizza provided

Thursday, October 27th
Dr. Windsor Morgan will present a planetarium show for the department

 "Welcome Back to the Kanev Planetarium!"

The Charles M. Kanev Planetarium is reopening, after being closed to the public in March 2020 at the beginning of the pandemic.  During the closure, the original analog "starball" and control system was replaced with a state-of-the-art digital projector and control system, Digistar 7. This is the first public showing, only for members of the Department of Physics and Astronomy and their students.

We will see only some of what the new system can do, including views of the sky, views from other parts of space, and fulldome movies.

Noon
Planetarium
Pizza provided beforehand from 11:30am-Noon in Tome 105

Thursday, November 17th
Dr. Olivia Harper Wilkins, Ph.D.
NASA Postdoctoral Program Fellow at NASA GSFC

"Astrochemical Perspectives from Interstellar and Terrestrial Laboratories"

The matter comprising our world, including life as we know it, was seeded by simple ingredients in the interstellar medium and the early stages of the Sun’s formation. But how that chemistry evolves over millions of years in extremely cold and diffuse environments is largely unknown. This talk explores observational and experimental work, from high-resolution chemical imaging using one of the largest radio telescope observatories in the world to cosmic ice analogue experiments under ultrahigh vacuum. Specifically, observations of methanol in an interstellar laboratory—the Orion Kleinmann-Low nebula—will be discussed in the context of understanding the nebula’s physical and chemical environment. In the terrestrial laboratory at NASA, rotational spectroscopy is used to study the gas-phase sublimated photoproducts of cosmic ice analogues formed and irradiated at interstellar temperatures of 10 Kelvin. Together, these investigations demonstrate some of the ways in which astrochemistry aims to answer astronomical questions.

Bio: Dr. Olivia Harper Wilkins ‘15 is a NASA Postdoctoral Program (NPP) Fellow at NASA Goddard Space Flight Center, where she conducts cosmic ice experiments. She earned a B.S. in Chemistry and Mathematics at Dickinson in 2015, after which she spent a year in Germany as a Fulbright Research Fellow. In December 2021, Dr. Wilkins earned her Ph.D. in Chemistry at the California Institute of Technology (Caltech), where she conducted observational astrochemistry research an NSF Graduate Research Fellow. She was also named an ARCS Scholar (2019-2021) and a 2022 CAS Future Leader. Dr. Wilkins is passionate about science communication and using art to share science, something that culminated in her writing and illustrating Astrochemistry for the American Chemical Society’s ACS In Focus series. She enjoys traveling with her husband and son and spending time at coffee shops.

Noon
Tome 115
Pizza provided