Registration Begins at 4:30 PM

Neutral atom quantum computing - past, present, and future 

Mark Saffman - University of Wisconsin-Madison and Infleqtion

In the last few years neutral atom quantum computing has evolved from a sleeper candidate to a  dark horse contender that may win the race towards utility scale quantum computing. I will highlight key steps in the development of neutral atom qubits, share a snapshot of where we are today,  and outline some of the challenges and potential solutions ahead of us. 

Trapped ion quantum computing

Phil Richerme - Indiana University

This talk will introduce how arrays of trapped atomic ions can be engineered and reprogrammed to compute the observable properties of quantum chemical systems. First, I will review some of the techniques we use to trap cold lattices of trapped ion qubits for quantum experiments. Next, I will focus on applications in quantum chemistry, where we have used trapped ion qubits to emulate hydrogen transfer dynamics within molecules and calculate their vibrational spectra to high accuracy. Finally, I will discuss our theoretical and experimental approaches towards addressing larger chemical systems with multiple correlated degrees of freedom, which quickly enter the regime of classical intractability.

Cold molecules as a platform for quantum science

Debayan Mitra - Indiana University

In recent years, cold and controlled molecules have enabled rapid developments in the fields of quantum simulation, chemistry and precision measurements of fundamental physics. Molecules provide unique features and challenges compared to their atomic analogs. They can strongly interact at long range due to their inherent dipole moments and provide internal states that are insensitive to external fields. Many molecular platforms have emerged in the last decade based on diatomic and polyatomic molecules. In this talk, I will discuss two avenues where molecular advantage plays a key role. 

First, I will discuss a novel molecular quantum gas microscope that is designed around a fermionic diatomic molecule. A majority of emergent natural phenomena in the solid-state are a result of entanglement due to strong interactions between electrons and its interplay with the underlying lattice structure. I will describe how the molecule MgF possesses many of the properties favorable to both laser cooling and single-site imaging. These molecules will interact via tunable dipole-dipole interactions while they quantum tunnel from site to site. I will describe how we plan to realize quantum magnetism Hamiltonians using such a platform. 

Secondly, I will show how we plan to take advantage of qualitatively different rotational modes of mercury based polyatomic molecules such as HgNH2 and HgOCH3 to measure atomic parity violation. Parity violation beyond the Standard Model is necessary to explain the absence of antimatter in the universe. However, particle accelerators probe electroweak interactions at high energy. We hope to complement the anapole moment measurement of 133Cs with 199Hg while leveraging the unique properties of polyatomic molecules for systematic reduction.

Towards fault-tolerant optical interconnects for neutral atom arrays

Josiah Sinclair - University of Wisconsin 

It has been recently shown that surface code error-corrected qubits can be connected with noisy links without requiring distillation, better local gates, or space-time overheads [1]. Combining recent advances in atom arrays with these results, I will report progress towards a flexible experimental platform for modular quantum computing comprising a programmable Rydberg atom array interfaced with an optical cavity. In such a platform, fault-tolerant scaling via noisy photonic interconnects can be achieved with two-qubit gate and Bell pair error thresholds of 1% and 10% respectively, as well as entanglement distribution fast enough to beat decoherence timescale.

1. J. Ramette, J. Sinclair, N.P.  Breuckmann, V. Vuletić. “Fault-tolerant connection of error-corrected qubits with noisy links” (2023), arXiv:2302.01296 [quant-ph]

Precision studies of radioactive molecules for nuclear science 

Shane Wilkins - Michigan State University and the Facility for Rare Isotope Beams

Despite its wide-ranging success, the Standard Model fails to explain multiple critical aspects of reality including the overwhelming dominance of matter over antimatter in the universe. The discovery of additional sources of CP-violation are thought to be needed to explain this matter-antimatter asymmetry which has remained an open question in nuclear science for decades.

Molecules containing heavy, deformed radioactive nuclei are premier candidates for next-generation experiments aiming to study the fundamental symmetries of nature in unprecedented detail. In these molecules, large increases in sensitivity resulting from the rare octupole deformation of certain radioactive nuclei can be combined with molecular structure enhancement factors to provide an unparalleled sensing capability to symmetry-violating nuclear properties.

Advances in experimental techniques have recently enabled the first laser spectroscopy study of molecules containing radioactive nuclei, despite their more complicated structures compounding their small production rates. This contribution will present recent results from subsequent experiments studying radium monofluoride at ISOLDE-CERN. A highlight of which includes the first observation of the distribution of nuclear magnetization in the structure of a molecule.

Session Two

A theorist's quantum simulations with neutral atoms

Ceren Dag - Indiana University

Unprecedented control of light-atom interactions presents a unique opportunity to physicists to prepare fundamentally interesting and technologically useful quantum states of matter. I will highlight two recent quantum simulations that we performed on remotely accessible Rydberg atom array of QuEra Computing. In the first one, we experimentally investigate the far from equilibrium physics of transverse-field Ising model, a prototypical model in statistical mechanics, and uncover significant deviations from the theoretical predictions. We theoretically traced this discrepancy to atom motion which acts as an emergent natural disorder in Rydberg atom arrays and elucidated our observations with a minimal random spin model. In the second quantum simulation, we prepared a multi-partite entangled state known as W state in quantum information science by employing quantum many-body physics of topological ring frustration. To demonstrate quantum coherence and entanglement in the experimentally prepared state, we developed a Bayesian state tomography protocol and bounded the measured state fidelity. These works also show that, as NISQ technologies advance, the gap between theory and experiment in quantum simulation is narrowing, ushering in an era where quantum simulation is becoming an essential tool in the theorist’s toolbox.

Towards ultracold KAg molecules for quantum simulation

Michael Vayninger (Yan Group) - University of Chicago

Ultracold molecules are an emerging platform for quantum science that combines the techniques of atomic physics pioneered over the last half century, including quantum-state control and single-particle detection/manipulation, with molecules' inherently rich internal structure. I will present new efforts at UChicago toward building novel quantum phases of matter using the emerging technology of highly polar molecules cooled to nanokelvin temperatures. Specifically, we hope to realize exotic topological superfluids built from interacting gases of KAg molecules, which could feature extraordinary characteristics such as resistance to disorder, frictionless flow, and the emergence of Majorana particles. We present progress for dual-species trapping of K and Ag atoms, sub-Doppler cooling of both species with Lambda-enhanced grey molasses, and the first realization of optical trapping of Ag atoms. Finally, we present our progress towards the evaporation of Ag atoms.

Programmable superradiance in an interacting superconducting qubit array

Qihao Guo (Ma Group) - Purdue University 

Superradiance is a fundamental phenomenon in quantum optics arising from the collective decay of quantum emitters. Despite its long history, understanding its microscopic dynamics remains an active frontier. Using the strong and tunable light–matter coupling in superconducting (SC) circuits, we engineer controlled collective decay of an interacting SC qubit array into a 1D microwave waveguide. We realize tunable superradiant and subradiant states and directly probe the emitters’ quantum states and correlations, revealing the microscopic dynamics of superradiance. Our results demonstrate a versatile approach for engineering collective couplings and open new avenues for exploring many-body physics in driven-dissipative quantum systems.

Lab Tours 

Observation of phase doubling and entanglement in coherent matter-wave reactions

Shu Nagata (Chin Group) - University of Chicago

Chemical reactions are conventionally regarded as incoherent processes governed by thermodynamics, where reactants evolve irreversibly into products. Here we show that in the quantum degenerate regime, where atoms and molecules form coherent matter waves, reactions can proceed as phase-matched many-body processes that preserve quantum coherence. Using molecular matter-wave diffraction, we observe phase doubling of the molecular wavefunction, confirming that coherence is transferred from reactants to products. The diffraction patterns further reveal non-classical correlations and entanglement between atom pairs created during the reaction. These results establish molecular matter-wave diffraction as a new probe of coherence and entanglement in reactive systems, and introduce matter-wave reactions as a platform for entanglement generation and coherent control of chemistry.

Ultra high-Q tunable microring resonators by slow light 

Ashwith Prabhu (Goldschmidt Group) - University of Illinois

Using spectral hole burning in erbium-doped lithium niobate microring resonators, we demonstrate ultra-high Q-factors exceeding 10⁸, enabled by strong material dispersion that dramatically reduces the group velocity. This slowdown increases the photon round-trip time, thereby extending the ringdown duration. Experimental observations are accurately captured by modified Bloch equations, which reveal an intensity-dependent dephasing rate approaching the radiative limit (T₂ → 2T₁) at higher optical fields. Additionally, we demonstrate MHz-level tunable optical filtering through electro-optic modulation, highlighting the device’s versatility for on-chip photonic applications. By extending the slow-light technique to waveguides, we achieve a temporal delay of nearly 300 ns with an internal efficiency approaching 3.5%. The current results showcase a promising platform that could enable efficient, scalable, telecom-band quantum delay lines

Versatile quantum sensing with Rydberg atoms 

Xinghan (Tony) Wang (Liang Group) - Purdue University

Rydberg atoms have emerged as a versatile platform for quantum sensing and precision measurement. In the first part of this talk, I will propose and experimentally demonstrate a calibration-free method for full 3D vector polarimetry, enabling simultaneous determination of field amplitude and frequency using a single spectroscopic measurement. In the second part, I will introduce a robust implementation of Rydberg anti-blockade via rapid adiabatic passage. This approach naturally generates avalanche excitation growth, which provides high gain with exceptionally low background, making it a promising tool for detecting rare events.

Searching for ultralight dark matter using atomic, molecular and optical physics techniques

Tejas Deshpande (Kovachy Group) - Northwestern University

One of the most significant challenges in fundamental physics is understanding the microscopic nature of dark matter (DM). Scalar ultralight DM (ULDM) is a well-motivated extension to the standard model (SM) of particle physics, hypothesized to interact with SM parameters like the electron mass and the fine-structure constant. As a result, the atomic, molecular, and optical physics community has focused considerable effort on ULDM detection using highly precise frequency metrology tools. This talk will introduce a novel optomechanical sensor utilizing two cryogenic sapphire Fabry-Pérot optical cavities designed to detect ULDM-induced length variations. A four-day observation period with this sensor achieved an improvement of up to two orders of magnitude in the limits to ULDM coupling to the SM for the ULDM's Compton frequencies ranging from 5 kHz to 100 kHz. This was demonstrated for both galactic halo and Earth-bound relaxion halo models. This work represents a crucial step towards future upgrades, which are projected to yield an improvement of up to five orders of magnitude over a wider frequency range (100 Hz to 1 MHz), ultimately surpassing the theoretical naturalness threshold.