Fall 2025 Colloquium Schedule
How to join
Colloquia are held on Thursdays in Webster Physical Sciences Building room 11 on the Pullman campus from 12:10 to 1:00pm.
Colloquia are held in person. For those who cannot attend in person, please join us on Zoom.
- Meeting ID: 965 8240 9398
- Passcode: physastro
Past colloquia can be viewed on our library on YouTube.
You can support these events by giving to the Physics Excellence Fund or the S. Towne Stephenson Lectureship.
Schedule
| Date 2025 | Speaker name, affiliation, and topic |
|---|---|
| Aug 21 | Brian Saam, WSU, State of the Department address |
| Aug 28 | Brian Collins, WSU, condensed matter |
| Sep 04 | Konstantin Matveev, WSU, cryogenic hydrogen systems |
| Sep 11 | Katherine Grier, Univ. Wisconsin, Madison, active galactic nuclei |
| Sep 18 | Jeff Vervoort, WSU, assembly of early earth |
| Sep 25 | Peter Schwindt, Sandia National Lab, quantum information |
| Oct 02 | Artur Widera, Rhineland-Palatinate Technical University of Kaiserslautern-Landau, quantum information |
| Oct 09 | Amin Chabchoub, Okinawa Institute of Science and Technology, marine physics |
| Oct 16 | Steven Furlanetto, UCLA, cosmology and galaxy evolution |
| Oct 23 | Chris Hamner, Univ. Hawaii, Bose-Einstein condensates |
| Oct 30 | Giorgia Busso, Univ. Cambridge, UK, Gaia mission overview and outlook |
| Nov 6 | Daniella DellaGiustina, Lunar and Planetary Laboratory, Univ. Arizona, OSIRIS-REX sample return mission early results |
| Nov 13 | Matthew McCluskey, WSU, physics of crystal colors |
| Dec 4 | Caroline Piaulet-Ghorayeb, Univ. Chicago, exoplanets |
Abstracts
December 3, 2025
“Beyond Earth 2.0: charting paths to habitable worlds with JWST”
The quest to understand whether planets beyond our Solar System could harbor life is a driving force in exoplanet science. Two principal types of exoplanets stand out as promising candidates for habitability. Temperate rocky worlds offer an exciting perspective as potential Earth 2.0s, but confident atmosphere detections on these planets still remain elusive. On the other hand, cool members of the “sub-Neptune” population – small planets distinct from Earth-like compositions, the most common in exoplanetary systems – may also harbor liquid water oceans albeit in exotic environments. In this talk, I will discuss recent advances in probing exoplanetary habitability, highlighting the need for a comprehensive approach that considers a planet’s internal makeup, its stellar environment, and the importance of 3D climate calculations to interpret observations. I will highlight recent JWST observations of TRAPPIST-1 d, a small temperate rocky planet, and share findings from JWST observations and novel modeling of small sub-Neptunes – results that prompt paradigm shifts in our understanding of the processes shaping these worlds.
November 13, 2025
“Physics of crystal colors”
While the intrinsic bandgap of a semiconductor can give it color, it is imperfections that account for the variety of optical properties seen in crystals. Electronic or vibrational transitions from impurities lead to well-defined features in the infrared (IR) spectrum. The famous Hope diamond contains boron acceptors that absorb from the IR into the red and green region of the spectrum, giving it a pale blue color. Color centers such as anion vacancies can be created by energetic particles, a useful effect for radiation dosimetry. Ruby and emerald get their red or green color from chromium impurities. Photochromism occurs when a crystal’s color changes after exposure to light. Photochromism (or photodarkening) is closely related to persistent photoconductivity and may originate from the same defect physics. Recent results on potassium tantalate, which show both of these persistent effects, will be discussed.
November 6, 2025
Daniella DellaGiustina
“Exploring Asteroids with the OSIRIS-REx Spacecraft and Samples”
NASA’s OSIRIS-REx mission became the first U.S. spacecraft to collect and return a sample from an asteroid, delivering over 120 g of material from (101955) Bennu to Earth in 2023. Early analyses reveal that Bennu’s rocks are rich in carbon, nitrogen, and water-bearing minerals, as well as unexpected magnesium-sodium phosphates – evidence that its parent body once hosted liquid water and complex chemistry. These findings illuminate the processes that shaped the early solar system and supplied the ingredients for life to Earth. Building on this success, the spacecraft has begun a new journey as OSIRIS-APEX to study asteroid (99942) Apophis when it passes extraordinarily close to Earth in 2029. Lessons from Bennu will guide this next encounter, offering a rare opportunity to watch an asteroid’s surface respond to strong tidal forces – and to deepen our understanding of how planetary bodies evolve and interact across the solar system.
October 30, 2025
Giorgia Busso
“The Ultimate Stellar Census: Inside ESA’s Gaia Mission”
Gaia is one of the most successful projects from the European Space Agency. Across more than 10 years since its launch, it has transformed our understanding of the Milky Way by precisely mapping the positions, motions, and properties of almost two billion stars. But Gaia also improved our knowledge of closer objects in our Solar System, with a survey of more than a hundred thousand asteroids, and of the furthest objects in the universe, with a catalogue of a few million quasars. I will introduce the Gaia mission concept, from the instruments to the data processing architecture. I will present a selection of the most important results obtained in the latest Gaia DR3 and finally give you a sneak peek at the coming DR4 in 2026.
October 23, 2025
Chris Hamner
“Optics and Photonics Engineering for Astronomy Applications”
A growing trend in astronomical instrumentation is the development of compact photonic devices to supplement traditional, large-scale optical systems. For these devices to be effective, light collected by a telescope must be efficiently coupled into few-mode waveguides for transport and analysis. My research focuses on combining free space, fiber based, and photonic circuit devices to realize high performance, compact and relatively low cost instrumentation. I will also discuss how our new faculty cohort, the Space Science and Engineering Initiative, is working to support ground based astronomy in Hawaii.
October 16, 2025
Steven Furlanetto
“How Much Do We Understand About Early Galaxy Formation”
The “Cosmic Dawn” of galaxy formation is one of the frontiers of modern astronomy. In the past two years, JWST has provided tantalizing clues about sources in the first several hundred million years of the Universe’s history that challenge our understanding this era, including an apparent overabundance of bright galaxies during the early phases, evidence for strong fluctuations in the star formation rate of sources, and a surprising abundance of accreting supermassive black holes. I will use a simple galaxy formation framework to describe how we can leverage these new observations to learn more abut this crucial era.
October 9, 2025
Amin Chabchoub
“Breathers and Rogue Waves Across Physical Systems”
Breather solutions of the nonlinear Schrödinger equation (NLSE), also known as solitons on finite or continuous backgrounds, have been known since the late 1970s. These pulsating, localized structures capture the nonlinear stage of modulational instability (MI) in a wide range of dispersive media and serve as canonical models for the emergence and control of rogue waves. This talk will review recent groundbreaking experimental observations of fundamental breather dynamics across optics, hydrodynamics, plasma, and Bose-Einstein condensates. Particular emphasis will be placed on applications in hydrodynamics, as well as the modeling and prediction of oceanic rogue waves. Furthermore, we report controlled laboratory observations of exact Manakov-type envelope solitons and breathers in a water wave basin. Despite the challenges associated with generating clean, reproducible crossing-wave conditions, the measurements exhibit excellent agreement with the integrable coupled-NLSE framework. Finally, perspectives will be offered on the broader role of MI in ocean wave dynamics.
October 2, 2025
Artur Widera
“Shaping Quantum Matter in Time: Floquet Engineering of Feshbach Resonances”
Understanding and controlling interactions is at the heart of modern quantum physics. Ultracold gases provide a unique playground for this, where magnetic Feshbach resonances allow us to tune how atoms interact. In this talk, I will introduce the basic ideas of laser cooling and quantum gases, and explain how Feshbach resonances work as a powerful tool to study collective quantum phenomena such as superfluidity and the BEC-BCS crossover. Building on this foundation, I will show how periodic driving – known as Floquet engineering, the time-analogue of Bloch’s theorem in solid-state physics – enables us to create and control entirely new resonances. Using ultracold lithium atoms, we realize Floquet-engineered Feshbach resonances through strong magnetic field modulation. The talk will connect fundamental concepts with cutting-edge experiments, providing both an accessible introduction and a glimpse into the frontiers of quantum engineering.
September 25, 2025
Peter Schwindt
“Measuring the Human Brain with Optically Pumped Atomic Magnetometers”
Over the past decade, optically pumped (atomic) magnetometers (OPMs) have proven to be an exciting new to technology for magnetoencephalography (MEG), the measurement of the magnetic fields produced by the active human brain and the localization of these neuronal currents. OPMs can be placed closer to the brain and can be worn offering new paradigms for MEG measurements for neuroscientists and clinicians. Since 2007, my group at Sandia has been developing OPMs, performing some of the first demonstrations of MEG with compact OPM sensor heads. I will present various aspects of our development efforts. I will describe our first multi-sensor OPM-MEG system where we implemented a 24-channel OPM system inside a person-sized magnetic shield. With the system, we have been able to localize neuronal sources and decode MEG signals using machine learning techniques to determine perceived speech in a closed vocabulary experiment. Next, I will discuss our most recent effort to implement a 108-channel optically pumped magnetometer (OPM) array in a magnetically shielded room. Our four-channel OPM has been redesigned to ease manufacturing, reduce the external temperature, improve the magnetic field control and uniformity, and reduce the required optical power, while maintaining or improving the sensitivity and bandwidth. We are in the final months of installing this system, and I show our most recent progress in this effort.
September 18, 2025
Jeffrey Vervoort
“Unraveling the Early History of the Earth”
In my research, I use the Hf and Nd isotope record of the early Earth to help better understand its early differentiation and how this relates to the formation and evolution of Earth’s earliest continental crust. A recent focus of my work is on the integrity of that isotope record: to what extent it has been modified by subsequent metamorphic events and how we can assess whether it faithfully records original isotope compositions. To answer these questions, I use coupled U-Pb age and Hf isotope analyses of zircon and U-Pb age and Nd isotope analyses of REE-rich phases (monazite, titanite, allanite, etc.) determined simultaneously by the laser ablation split-stream (LASS) method. Our research indicates that the formation of long-lived continental crust and
corresponding depletion of the mantle did not occur significantly until after about 3.8 Ga.
September 11, 2025
Kate Grier
“Probing Supermassive Black Holes and Quasars with the SDSS-V Black Hole Mapper Reverberation Mapping Project”
One of the major areas of exploration in astrophysics is the study of how galaxies form and evolve. All massive galaxies have a supermassive black hole at their center, and observations suggest that the growth of the galaxies and their central supermassive black holes are linked. In order to understand how galaxies evolve, we thus also need understand how their central black holes grow and how these black holes interact with their host galaxies. To do this, we use observations of active galactic nuclei and quasars, which are actively accreting supermassive black holes that emit a tremendous amount of energy, visible across the entire observable universe. The Sloan Digital Sky Survey (SDSS) is monitoring thousands of quasars over more than decade to explore supermassive
black holes and quasars at a wide range of distances. We have collected hundreds of spectra each for thousands of quasars as a part of the SDSS-V Black Hole Mapper Reverberation Mapping Project (BHM-RM). While the main goal of this program is to measure black hole masses using a technique called reverberation mapping, these spectra have also allowed us to explore variability in quasars and learn about supermassive black holes from numerous different angles, ranging from studies of broad absorption-line variability in quasar spectra, to studies of extreme variability events. I will give an overview of the BHM-RM project and highlight some of the work that we have been doing that has been enabled by this unprecedented spectral dataset.
September 4, 2025
Konstantin Matveev
“Modeling of thermofluid processes in liquid hydrogen storage and transfer systems”
Hydrogen is a promising clean and renewable fuel that can help humanity impede the catastrophic climate change. However, to produce, store, and transport hydrogen in the energy-dense liquid form, low cryogenic temperatures are required, as hydrogen boils at about 20 K. Investigation and characterization of liquid hydrogen processes, components, and systems represent the main R&D directions of the Hydrogen Properties for Energy Research (HYPER) Center at Washington State University. In this talk, our efforts on modeling thermofluid phenomena involving cryogenic and liquid hydrogen will be presented. The employed modeling methods range from lumped-element models to high-fidelity computational fluid dynamics simulations. The discussed applications include dynamic processes in liquid hydrogen storage tanks, critical phase-changing flows, para-orthohydrogen conversion for cryocooling, Taconis oscillations that lead to large heat leaks into cryogenic tanks, multiphase flow instabilities important for transferring liquid hydrogen, and other unsteady phenomena. The developed models can help engineers optimize design and operations of liquid hydrogen systems with higher confidence.
August 28, 2025
Brian Collins
“Exploring Molecular Devices and Nanostructures with Resonant X-rays”
Printable, flexible, and biocompatible polymers and small molecules represent an exciting new class of materials with the potential to revolutionize energy technologies, computing, bio-interfacing, and medicine. A grand challenge for progress, however, is in characterizing the molecular-to-mesoscale ordering that governs excited state dynamics and performance but often confounds traditional nanoprobes. I will discuss our work in developing resonant X-rays to break through this barrier applied to organic electronics and aqueous micelle nanocarriers. We combine device physics with X-ray characterization to investigate emergent interfacial excited states in solar cells and develop resonant X- ray optical models to track interfacial molecular orientation. In biosensors, we have revealed that hydrophilic ion nanochannels can result in new record ion mobilities, gated by local chemical signaling. Finally, I will describe our development of microfluidic environments to probe aqueous micelle nanocarrier chemical ordering and dynamics in a smart medicine platform. With continued development, resonant X-rays will be key to controlling unique properties in soft matter that depend on spatiochemical nanoscopic order for exciting new applications beyond the reach of current materials and technologies.
August 21, 2025
Brian Saam
“State of the Department”
The whole department – faculty, staff, students, and anyone else sharing in our common mission and purpose – is invited to help kick-off the new academic year with the department chair’s annual report and charge for the coming year. This will not be a technical physics/astronomy colloquium but rather a review of the past year’s highlights, an introduction to new members of the department, and a brief statement of the chair’s outlook for the coming academic year and beyond. As always, there will be time for questions, concerns, and heckling.