We are an experimental ultracold atomic physics group in the Physics department at UC Santa Barbara. Our group uses quantum degenerate gases to explore a wide variety of quantum mechanical phenomena. Research interests include quantum interactive dynamics, quantum thermodynamics, quantum quasicrystals, Floquet engineering, and quantum metrology.
Weld Group Updates
The results of our experiment exploring light-induced phases of 2D materials in a modulated 1D quasicrystal are available on the arXiv.
Our paper demonstrating noise-tolerant trapped matter-wave interferometry in Floquet-Bloch bands is on the arXiv.
Peter's new design for a robust high-temperature atomic beam source is published in RSI.
Yifei's theory paper on quantum simulation of quantum Hall matter driven by arbitrarily polarized light, featuring an MC-Escher-like tesselated localization phase diagram, is published in PRB.
Our experimental results exploring a "double-localization" phase diagram controlled by the interplay of disorder and driving are published in PRR.
Results from our collaboration with the Moody and Bowers groups on photonically-integrated lasers for atomic physics applications are published in APL Photonics.
Our paper on reversible phasonic control of a quantum phase transition in a quasicrystal is published in PRL.
Congratulations to Weld lab undergraduate researcher Xuanwei Liang on receiving a 2024 Goldwater scholarship!
Our paper reporting the observation of anomalous localization and multifractality in the kicked Aubry-André-Harper model (a collaboration with theorists Tarun Grover and Peter Lu) has been published in Nature Physics. See also a nice accompanying viewpoint article by Julian Léonard.
A paper on quantum simulation of high-harmonic generation (a collaboration led by Maciej Lewenstein's theory group) is published in PRX Quantum.
A paper on laser-induced contamination of diamond-vacuum interfaces (a collaboration with the Mukherjee and Jayich groups) is posted on the arXiv.
Our paper demonstrating a thermodynamic engine with a quantum degenerate working fluid (a collaboration with the group of Glenn Fredrickson) has been published as a letter in Phys. Rev. Research.
David has been selected by the Gordon and Betty Moore Foundation as one of its 2023 Experimental Physics Investigators.
Congratulations to Weld lab alumnus Jacob Van Arsdale on receiving a Goldwater scholarship!
Our paper on the emergence of chaos in an interacting quantum kicked rotor (a collaboration with Victor Galitski) has been published in Nature Physics. See also the accompanying viewpoint on "Kicked rotors back in action," a "behind the paper" blog post, and nice popular summaries here and here.
David is the lead PI for a newly-awarded NSF NRT graduate training program at UCSB, called Integrative Training in Quantum Assembly & Technology (InTriQATE).
A paper reporting extended qubit coherence via spectrally engineered driving of the environment (a collaboration with the group of Ania Bleszynski Jayich) is published in NPJ Quantum Information.
David has been elected to the executive committee of DAMOP, jewel of the APS.
Our paper reporting the first experimental observation of the quantum boomerang effect (a collaboration with the groups of Tommaso Macrì and Patrizia Vignolo) has been published in PRX and highlighted in Physics. Science News also has a good article about the result.
Our paper written in collaboration with Cenke Xu's group proposing experimental realizations of fractal order has been published in Phys. Rev. Letters.
The Weld group is one of many contributors to a new Roadmap on Integrated Quantum Photonics, led by Galan Moody and now published in J. Phys. Photonics.
David is the 2020-2021 recipient of the Chancellor's Faculty Award for Undergraduate Research Mentoring, and Alec has won a Chancellor’s Award for Excellence in Undergraduate Research (link).
Congratulations to Weld lab undergrad Alec Cao, who has won a 2021 Churchill Scholarship! Alec will be working with the group of Zoran Hadzibabic at Cambridge.
David's take on "an atom's-eye view of quantum information processing," presented at the first CIQC colloquium, is available on YouTube.
The Weld group is excited to be participating in the new DOE-supported Quantum Science Center, of which David is the co-design lead for quantum simulation.
In collaboration with our CAIQuE colleagues at Berkeley, UCLA, and elsewhere, we're thrilled to be part of a new computing-focused Quantum Leap Challenge Institute supported by the National Science Foundation.
Our paper studying connections between transport and Poincaré orbit topology in inhomogeneous driven lattices has been published as a Rapid Communication in Phys. Rev. Research. See also this nice news article on the result.
Congrats to Alec and Max on being named Goldwater Scholars! The Weld group is tied with Princeton University for 2020 Goldwater Scholarships.
Alec's paper on non-exponential decay has been published in Zeitschrift für Naturforschung A as an invited contribution to a special issue on "Physics of Non-Equilibrium Systems."
Our paper reporting phasonic spectroscopy of a tunable quantum quasicrystal has been published in PRL.
Congratulations to Dr. Cora Fujiwara on a successful dissertation defense! Cora is joining Joseph Thywissen's group at the University of Toronto for a postdoc.
Our paper reporting experimental control and characterization of Floquet prethermalization has been published in
Congratulations to Dr. Shankari Rajagopal on a successful dissertation defense! Shankari will join the Schleier-Smith group at Stanford for a postdoc.
Congratulations to Dr. Kevin Singh on a successful dissertation defense! Kevin is joining the Bernien group at U Chicago for a postdoc.
Our paper reporting Floquet band engineering of long-range transport and direct imaging of Floquet-Bloch bands has been published in Phys. Rev. Letters.
BIFROST, a new ARO-supported multi-user distributed tunable laser facility, is up and running (article). This unique instrument was conceived and commissioned by the Weld group in collaboration with 8 other UCSB experimental groups.
Congratulations to Dr. Ruwan Senaratne on a successful dissertation defense! Ruwan will join the Hulet group at Rice as a postdoc.
Our paper reporting the experimental realization of a relativistic harmonic oscillator has been published in New Journal of Physics. Now featuring a video abstract by Cora!
The lithium team's paper describing the experimental observation and uses of position-space Bloch oscillations (a collaboration with theorists at Lisbon and Paderborn) has been published as an Editor's Selection in Phys. Rev. Letters and spotlighted with a commentary on the APS Physics website.
Ruwan and Shankari's paper on experimental quantum simulation of ultrafast dynamics with ultracold strontium has been published in Nature Communications.
Our collaborative project with Sumita Pennathur's group recently demonstrated a new class of energy harvester. The paper has been published in Phys. Rev. Applied.
Congratulations to Dr. Zachary Geiger on a successful dissertation defense! Zach will be joining the technology development team at Intel.
Motivated graduate students and postdoctoral researchers interested in working with our group should email David Weld.