Past Events

Abstract: Magnetism is a striking example of how quantum mechanics and interactions among electrons combine to generate entirely new forms of collective behavior—phenomena that deepen our understanding of matter, as well as power modern technologies. Over the past decades, discoveries in magnetism have often heralded new paradigms in condensed matter physics, exemplified by antiferromagnetism and Mott insulators, and quantum spin liquids with their fractionalized excitations. In real materials, however, spins are inseparable from the crystalline lattices that host them.

The corona is a layer of hot plasma that surrounds the Sun, traces out its complex magnetic field, and ultimately expands into interplanetary space as the supersonic solar wind. This complex and unpredictable system varies over many orders of magnitude in space and time, so it's not surprising that we still do not have a complete theoretical understanding of its origins. In this talk, I will present some new observations and theoretical concepts that are helping us get closer to finally identifying and characterizing the physical processes responsible for the corona and solar wind.

Abstract: Non-methane volatile organic compounds (NMVOC) are emitted into the Earth’s atmosphere by varied biogenic and anthropogenic sources. Though the concentrations of these compounds are minute, they exert an outsized influence on atmospheric composition, primarily through their oxidation chemistry. This chemistry leads to the formation of key secondary species including tropospheric ozone, a harmful pollutant, and secondary organic aerosol (SOA), a key component of atmospheric particulate matter with implications for climate and air quality.

Abstract:  Interacting electrons in strong magnetic fields give rise to rich phenomena, exemplified by the quantum Hall effect. In rhombohedral graphene, remarkably similar behavior has been observed even without an external field. In this talk, I will describe how electron–electron interactions in this system can spontaneously generate giant effective magnetic fields, reaching hundreds of Tesla. These emergent fields originate from self-organized layer-skyrmion textures, whose dynamics give rise to distinctive collective shape modes that can be experimentally probed.

The Department of Physics at the University of Colorado Boulder in collaboration with CUbit and JILA is hosting the third annual Physics and Quantum Career & Internship Fair on Friday, October 17^th from 12:00 - 3:00 p.m. in the Glenn Miller Ballroom.

This event will feature employers across all areas of theoretical, experimental, and computational physics. The fair will connect physics undergraduate and graduate students and recent alumni with laboratory and industry leaders to learn about internships and employment opportunities.

We have developed a new cloud model, CARMA Cloud, for the NCAR Community Earth System Model that is designed to simplify the cloud model and improve its representation of cloud aerosol interactions. Rapid, unexpected, global warming since 2003 seems to be due to a combination of cloud feedback to global warming and strong response to aerosol changes. While the model is currently aimed at terrestrial cloud physics, the basic code has recently been used for exo-planet studies, and an early version of the model was used for studies of Martian ice clouds.

Abstract: Strongly correlated and topological phases in condensed matter systems are at the cutting edge of fundamental physics studies, as well as being promising candidates for the next generation of technological capabilities like quantum computing. In recent years, a remarkable amount of progress has been made in creating and controlling such phases by introducing a small twist angle or lattice mismatch between two-dimensional (2D) materials.

Abstract: With the advent of the Gaia space mission, there has been a revolution in astronomers’ ability to precisely locate the interstellar structures the Sun may have encountered on its voyage around the galaxy. We now have the spatial resolution to trace the Sun’s trajectory back through its interstellar environment up to 60 million years in the past (4000 light-years in distance). This timescale is commensurate with the timescale over which we can reconstruct the paleoclimate of Earth from deep ocean foraminiferas.

Parkinson’s Disease (PD) is the second most prevalent neurodegenerative disease, affecting ~10 million people worldwide. One of the most commonly mutated genes in PD codes for Leucine Rich Repeat Kinase 2 (LRRK2). Autosomal dominant mutations in LRRK2 cause familial PD, while mutations in LRRK2 are risk factors for sporadic PD and increased activity of LRRK2’s kinase has been linked to the sporadic form of the disease as well. This has made LRRK2 the main actionable target for PD therapeutics.

Please join us for a JAGS Industry Spotlight Seminar featuring Micron. A networking session with the speaker will take place at 12:30pm followed by a technical presentation about the ongoing projects. 

Parker Solar Probe successfully completed its prime mission in 2025, measuring solar wind plasma in-situ as close as 8.8 solar radii (~0.04 AU) from the solar photosphere over a series of close-approach orbits. These close approaches to the Sun enable novel exploration of fundamental stellar processes, such as solar wind acceleration, solar wind heating, interplanetary dust destruction, and radial evolution of solar surface structure. These processes leave distinct signatures in near-Sun particle and field observations that allow us to untangle the physical mechanisms driving them.

Abstract: Polaritons are hybrid light-matter states with unusual properties that arise from strong interactions between a molecular ensemble and the confined electromagnetic field of an optical cavity. Cavity-coupled molecules appear to demonstrate energetics, reactivity, and photophysics distinct from their free-space counterparts, but the mechanisms and scope of these phenomena remain open questions. I will discuss new experimental platforms that the Weichman Lab is developing to investigate molecular reaction dynamics under strong cavity coupling.

Abstract: Magnetism is the posterchild of how the interplay between electron-electron interactions and quantum physics promotes novel macroscopic phenomena. Historically, the evolution of our understanding of magnetism has been related to the discovery of new paradigms in condensed-matter physics, as exemplified by the connections between antiferromagnetism and Mott insulators, spin glasses and non-ergodic states, and spin liquids and fractionalized excitations.

While photophoresis, or “light-driven motion,” has long explained how aerosol layers remain aloft in the middle atmosphere, practical applications have only recently been gaining attention. Advances in nanofabrication now allow us to build lightweight structures that can propel themselves upward using photophoretic forces alone. These “photophoretic flyers” can sustain flight in near-space (30–100 km altitudes), a region that is too high for aircraft and balloons and too low for satellites.

Abstract: The development of pulsed Electron Spin Resonance (ESR) spectroscopy at microwave frequencies above 100 GHz remains a challenging and costly task, primarily due to the limited output power of modern high-frequency solid-state electronics. Nonetheless, a range of critical scientific problems—such as dynamic nuclear polarization (DNP) enhancement of NMR and quantum computing applications involving electron spins—necessitate spin relaxation measurements at THz frequencies.

Abstract: CryoEM and cryoET enable imaging of biological specimens frozen in vitreous ice, revealing 3D molecular or cellular structures at high resolution and in their native state. However, cryoET is limited by the “missing-wedge” problem due to restricted tilt angles, and cryoEM often suffers from preferred orientation, resulting in uneven sampling of angular views and leaving parts of Fourier space poorly covered.

Abstract: Modern metrology involves a tight integration of sensors with computation. Suppose that a quantum computer were inserted into this pipeline as the first step in receiving and transforming sensor signals, before classical processing. What could be accomplished?  I illustrate the possibilities with three scenarios for which quantum computation may enhance sensing: demodulation of phase shift keyed signals, trajectory discrimination, and RF signal detection.

The Department of Biochemistry invites professors and scientists from other universities and institutes to present seminars at the University of Colorado Boulder throughout the academic year. These seminars provide an opportunity for faculty and students to learn about exciting current research.

The launch and commissioning of the James Webb Space Telescope is ushering in a new era in our understanding of our cosmic origins. Galaxies are a fundamental building block of the universe, yet how they formed has remained enigmatic owing to our inability to observe them at early cosmic times. In just its first three years of operation, JWST has already upended our understanding of galaxy and black hole growth in the early universe.

Abstract: The tiny particles that comprise almost all the mass in our bodies as well as the stars and planets are held together by a force so strong that it is nearly impossible to break away from it. It’s so strong that if you try to break the glue bond, you’ll create anti-matter particles!