JILA Auditorium

High fidelity quantum logic on two trapped-ion qubits without ground-state cooling

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Oxford Ionics develops trapped-ion quantum computers.  We are UK headquartered and opened our US office in Boulder last year.  We will present the work we do in Boulder developing our architecture and our future plans to open a lab and  grow the team here.  We will also discuss our recent acquisition by IonQ and what it means for the companies' joint roadmap.

Toward a Rational Understanding of Polariton Chemistry

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Mid-Infrared (MIR) light can interact with molecules by selectively exciting molecular vibrational modes. In combination with photonic structures, MIR can target specific vibrational states of molecular to influence chemical reactions. In this talk, I will explain how photonic environments can modify molecular dynamics through strong light-matter coupling. This strong coupling leads to the molecular vibrational polaritons – a hybrid quasiparticle between light and matter.

2 Fast, 2 Furious? Galaxy and Black Hole Formation in the JWST Era

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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.

Steering spin–valley polarizations through phonons and photons

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Control of spin and valley polarizations opens opportunities for spintronic and quantum information applications. Monolayer transition-metal dichalcogenides (TMDs) offer an appealing platform to harness such polarizations. TMDs host excitons in valley-shaped regions of their band structure, featuring well-defined carrier spins and obeying chiral optical selection rules. However, the technological potential of excitons in TMDs is impeded by rapid spin–valley relaxation.

Exploring the Fates of Atmospheric Peroxy Radicals with Model- and Computation-informed Environmental Chamber Experiments

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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.

There and Back Again: A Journey to the Sun

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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.

New Experimental Platforms for Molecular Polaritonics

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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.

Zooming In: Single-Particle Insights into Nanomaterials for Energy Conversion and Storage

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Abstract: My talk will highlight new directions in probing semiconductor electrochemistry and reactivity at the single-particle and single-molecule level. I will discuss our recent discovery that the band gap renormalization (BGR) effect in 2D semiconductors strongly dictates their current–voltage behaviorin electrochemical cells, providing a new framework to understand solid-state transistor device performance variability.

AI-Driven Quantum Mechanical Design of Soft Materials

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Abstract: While the properties of soft materials are ultimately dictated by their electronic structure, exploiting this knowledge for the design of non-crystalline materials has long been a formidable computational challenge. I will define conceptual and practical barriers that limit quantum mechanical design in soft materials and discuss recent work aimed at removing these barriers. First, I will describe the development of electronic structure models that leverage AI to operate at coarse-grained resolutions, enabling electronic design in non-crystalline molecular solids and polymers.

Realizing lossless energy flow in semiconductors at room temperature

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Abstract: Achieving ballistic, coherent charge and energy flow in materials at room temperature is a long-standing goal that could unlock ultrafast, lossless energy and information technologies. The key obstacle to overcome is short-range scattering between electronic particles and lattice vibrations (phonons). I will describe two promising avenues for realizing ballistic transport in two-dimensional (2D) semiconductors by harnessing hybridization between electronic particles and long-wavelength excitations.