Past Events

A Transportable Ytterbium Optical Lattice Clock with Eighteen Digits of Accuracy

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Abstract: 

We present the development and uncertainty evaluation of a transportable ytterbium optical lattice clock, achieving a total systematic uncertainty level of 3.7 ×10-18. We also report a field test of the clock after transporting it to Washington DC, demonstrating the clock’s reliability and readiness to contribute to scientific efforts such as the redefinition of the SI second and frequency-based measurements of Earth’s geopotential.

SPEED!

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Cornell 2024

Join one of CU Boulder’s beloved Nobel Laureate Professors, Eric Cornell on a journey through space, all in good time!  “Speed!

Adiabatic passage and geometric phases: are they hot or not?

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In this informal seminar I will present an appraisal of adiabatic passage which transforms quantum states much better than one should expect (and I will explain why this is the case). And I will discuss an often stated claim that geometric phases, used in many  gate proposals for quantum computing, are particularly robust because of their geometric character (and I will explain why I think this is not the case).

STROBE 2024 NSF Site Review: Audit Results and Lessons Learned

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Join us for a presentation about the recent STROBE NSF Site Review that took place in January 2024. From an institute perspective, this presentation will cover the entire timeline of the review, the types of inquiries and CU's response to the review team, and best practices and tips for working with reviewers. Discussion and question/answer will follow the presentation. All are welcome!

Coherent Control of Metastable States - A View from Behind the Computer Screen

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Creating, understanding, and controlling metastable states of quantum matter is highly interesting due to the prospects of enabling ultrafast and energy efficient devices with novel functionality. Recent estimates indicates that non-thermal pathways to metastable phases may require several orders of magnitude less energy than a thermally driven process. In addition, hidden states of matter may be accessed if a system out of equilibrium follow trajectories to a state inaccessible, or nonexistent, under normal equilibrium conditions.

A high optical access cryogenic optical tweezer array

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Abstract: Arrays of single trapped neutral atoms are an important platform for quantum metrology, simulation, and information processing. Interacting Rydberg atom arrays have undergone rapid scaling in qubit numbers and improvements in coherent control in recent years. Placing Rydberg atoms inside a cryogenic environment is of interest for reducing background gas collisions and blackbody radiation-induced decay.

Realization of a Quantum-Optical Spin Glass

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Abstract: Spin glasses—large-scale networks of spins with deeply frustrated interactions—are canonical examples of complex matter. Although much about their structure remains uncertain, they inform the description of a wide array of complex phenomena, ranging from magnetic ordering in metals with impurities to aspects of evolution, protein folding, climate models, and combinatorial optimization. Indeed, spin glass theory forms a mathematical basis for neuromorphic computing and brain modeling.

Effective field theories for phases of matter and cosmology

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Abstract: I will review some modern applications of effective field theories outside their traditional particle physics domain. In particular, I will focus on spontaneous symmetry breaking for spacetime symmetries. The effective theories for the associated Goldstone excitations capture the low-energy/long-distance dynamics of a number of physical systems, from ordinary macroscopic media (solids, fluids, superfluids, supersolids) to more exotic cosmological ones.

Quantum computing with Yb Rydberg atoms

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Abstract: Neutral atom quantum computing is a rapidly developing field. Exploring new atomic species, such as alkaline earth atoms, provides additional opportunities for cooling and trapping, measurement, qubit manipulation, high-fidelity gates and quantum error correction. In this talk, I will present recent results from our group on implementing high-fidelity gates on nuclear spins encoded in metastable 171Yb atoms [1], including mid-circuit detection of gate errors that give rise to leakage out of the qubit space, using erasure conversion [2,3].

Postdoctoral and Early-career Association of Researchers-Boulder Monthly Seminar: JILA edition

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Please join us for a special edition of our PEAR Boulder monthly seminar series on Tuesday, April 30th at 11 am MT (1 pm ET) in conference room 1-1107 or online at https://nist.zoomgov.com/j/1601226156?pwd=aWpSMklZRWNxWGxLWXFmVVdRMEQrU….

We have two speakers from JILA (Joint Institute for Laboratory Astrophysics), Jacob S. Higgins and Kyungtae Kim, both from Prof. Jun Ye’s research group. JILA is a joint institute between NIST and the University of Colorado Boulder.

Forming truncated accretion disks

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Abstract: Black hole X-ray binaries and Active Galactic Nuclei transition through a series of accretion states in a well-defined order. During a state transition, the accretion flow changes from a hot geometrically thick accretion flow, emitting a power-law–like hard spectrum to a geometrically thin, cool accretion flow, producing black-body–like soft spectrum.

Tabletop Coherent Extreme Ultraviolet Metrology and Imaging of Nanostructures

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Abstract: Nanoscale fabrication has progressed to the level where detailed near nanometer structure can be routinely produced. As fabrication scales shrink to atomistic scales, a corresponding need for high precision characterization is in demand. The use of extreme ultraviolet light (EUV) for patterning of small-scale features has seen considerable development and application in recent years.

POSTPONED to Fall 2024: Rare earth and other critical elements - their physics, resources, and geopolitics

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Abstract: The rare earth elements, hidden at the bottom of the periodic table and long neglected, have risen to prominence at the end of the 20th century. Their unique electronic configuration form the basis for a variety of lasers, photonic applications, strong and exotic magnetism, defining many modern technologies. I will tell a story connecting from the basic science of the geology of Colorado and rare earth and other rare element mineralogy, to our technological and societal dependence and questions of strategic element security. 

Visualizing Dynamics—A Role for Nonlinear Optical Spectroscopy in Energy Science

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Abstract: The climate crisis is driving a new era of electrification around the globe.  The decarbonization of transportation and industrial processes is expected to make a significant impact on the rate of climate change.  For example, the electrification of refineries and the broader chemical industry has the potential to lead to major reductions in fossil fuel consumption and lower the production of harmful greenhouse gases contributing to climate change.  New components including electrode materials and electrolytes are being discovered quickly and are necessary to engi