arXiv subjects

Zane Ozzello

Publications and source records attributed to Zane Ozzello.

8 recordsLinked to original sources

arXiv2026

Confinement and String Breaking in the Compact Abelian Higgs Model

While real-time simulation of Quantum Chromodynamics remains technologically out of reach, simplified models for studying elements of QCD phenomenology abound. This work presents a simple model, a spin-1 truncation of the Compact Abelian Higgs Model simulated on qutrit sites, in which confinement and string breaking is accessible to current simulation methods. In the low-energy regime of 1+1D scalar electrodynamics, the heavy modes are integrated out, producing a spin chain effective Hamiltonian in which Gauss' law is implicitly satisfied. We study the spectrum of string-like excitations using DMRG methods on the order of 100 sites. We demonstrate that an added, local chemical potential, playing a role analogous to external charges, permits parameter-dependent measurements of physical features of interest like the string tension and effective meson mass. Varying the chemical potential also permits a characterization of string stability not assessed in prior studies of confining lattice models.

hep-lat↗

arXiv2026

Finite size scaling of bitstring probability distributions for Rydberg arrays

We calculate the probabilities $p_{\{n\}}$ of the measured bitstrings $\{n\}$ for the vacuum of Rydberg ladders with $N_q$ atoms. As $N_q$ increases, the $p_{\{n\}}$ decrease but become more dense in the low $p$ region raising the possibility that their smallness could be compensated by their large number. The importance of the low probability states can be estimated from the cumulative probability distribution $\Sigma(p_{\Lambda},N_q)$, which is the probability to observe any state having a probability $p\leq p_{\Lambda}$. For not too large values of $p_{\Lambda}$, it is possible to approximately collapse the $\Sigma(p_{\Lambda},N_q)$ for successive $N_q$ into a function resembling the Fermi function when plotted as a function of $-\ln(p_{\Lambda})$. We show that the number of shots necessary to reduce $\Sigma(p_{\Lambda},N_q)$ to some low enough value grows exponentially with $N_q$. We discuss the implications for calculating observables associated with the vacuum.

quant-ph↗

arXiv2026

Hybrid Analog-Digital Simulation of the Abelian Higgs model

To investigate gauge theories with near-term quantum computers warrants exploration of nontraditional quantum simulators to find resource-efficient simulation protocols and ultimately access exotic features of different field theories, including unexplored regimes of the QCD phase diagram. In this work, using superconducting transmon qutrit processors, we formulate and implement a pulse-based, three-level, hybrid analog-digital simulation protocol of the (1+1) dimensional Abelian Higgs model (AHM) on two sites. Alongside this approach, we experimentally realize a gate-based implementation of the same model. Using the natural mapping of the three-level truncation of the transmon Hilbert space to the spin-1 truncated AHM, we observe real time dynamics of AHM field observables, which are analogous to electric field operators, with both protocols. For the analog-digital protocol, we engineer a Floquet simulation with a combination of local analog drives, driven modification of the natural interaction Hamiltonian of the two transmons, and dynamical decoupling pulses. For the digital protocol, we use a state-of-the-art qutrit processor to implement a Trotterized simulation of the model incorporating advanced error mitigation techniques. We further discuss the scalability of the two approaches, and their potential to be extended to the simulation of other model Hamiltonians. Our experiments demonstrate a viable platform for future studies of spin-1 and SU(3) based gauge theory models on current and near-term transmon qutrit processors.

quant-ph↗

arXiv2025

Multipartite entanglement from ditstrings for 1+1D systems

We show that multipartite entanglement can be used as an efficient way of identifying the critical points of 1+1D systems. We demonstrate this with the quantum Ising model, lattice $\lambda \phi^4$ approximated with qutrits, and arrays of Rydberg atoms. To do so we make use of multipartite compositions of entanglement quantities for different parts combined to form the strong subadditivity, weak monotonicity, and a convex combination of these with conformal properties. These quantities display some remarkable properties. We will demonstrate how the entanglement of individual parts together displays behavior at phase boundaries, but the combination of these in the aforementioned quantities sharpens and localizes this behavior to the boundaries even better. We will show that we can extend a scheme for approximating the entanglement with the mutual information, and that this acts as a lower bound which will also follow the changes in the entanglement for the above quantities, despite the additional contributions of different signs. This mutual information approximation to the identifying quantities can have its lower probabilities removed in a process we call filtering, and despite the combination of terms will respond well to the filtering and offer improvements to the lower bound.

quant-ph↗

arXiv2025

Diagnosing Device Performance in Rydberg-Ladder Gauge Simulators with Cumulative Probabilities and Filtered Mutual Information

We study bitstring measurements from the publicly available Aquila Rydberg-atom platform using a two-leg ladder that encodes a truncated lattice gauge model as a practical benchmark that can be directly implemented and simulated on current hardware. Our goal is diagnostic: we analyze how errors propagate into bitstring probability distributions and downstream information measures, focusing on ladders with 6, 8, and 10 rungs and $\mathcal{O}(10^3)$ shots. We introduce cumulative probability distributions as a compact way to compare Aquila data with high-accuracy density matrix renormalization group (DMRG) and exact references, and we use optimally filtered mutual information primarily as a robust device-data diagnostic rather than a direct entanglement estimator. By isolating finite sampling, sorting fidelity, adiabatic ramp-up, Rabi-frequency ramp-down, and readout errors, we find that readout mitigation performs well in controlled DMRG tests. Applying the same procedure on hardware shows accuracy limitations for the leading probabilities estimation, indicating that readout errors are not dominant and that residual error is instead driven by imperfect state preparation.

quant-ph↗

arXiv2024

Improved entanglement entropy estimates from filtered bitstring probabilities

Using the bitstring probabilities of ground states of bipartitioned ladders of Rydberg atoms, we calculate the mutual information, which is a lower bound on the corresponding bipartite von Neumann quantum entanglement entropy $S^{vN}_A$. We show that in many cases these lower bounds can be improved by removing the bitstrings with a probability lower than some value $p_{min}$ and renormalizing the remaining probabilities (filtering). We propose a heuristic based on the change of the conditional entropy under filtering that very effectively improves the estimate of $S^{vN}_A$. We consider various sizes, lattice spacings and bipartitions. Our numerical investigation suggest that the filtered mutual information obtained with samples having just a few thousand bitstrings can provide reasonably close estimates of $S^{vN}_A$. We briefly discuss practical implementations with QuEra's Aquila device.

quant-ph↗

arXiv2023

Bootstrap methods for digitized scalar field theory

General positivity constraints linking various powers of observables in energy eigenstates can be used to sharply locate acceptable regions for the energy eigenvalues, provided that efficient recursive methods are available to calculate the matrix elements. These recursive methods are derived by looking at the commutation relations of the observables with the Hamiltonian. We discuss how this self-consistent (bootstrap) approach can be applied to the study of digitized scalar field theory in the harmonic basis. Using known results, we develop the method by testing on quantum systems, including the harmonic and anharmonic oscillators. We report recent numerical results for up to four coupled anharmonic oscillators. From here, we consider the possibility of using the groundwork of this method as a means of studying phase transitions in 1+1 dimensions.

hep-th↗

arXiv2022

Prolegomena to a hybrid classical/Rydberg simulator for hadronization (QuPyth)

Programmable neutral-atom arrays provide a promising route to real-time analog simulation of strongly interacting quantum systems. We introduce a two leg Rydberg atom ladder that realizes string dynamics and controllable particle production using experimentally accessible parameters. A mapping between local Rydberg occupations and an emergent electric field yields charge anticharge pairs connected by dynamical strings. Classical simulations enforcing Rydberg blockade constraints identify regimes with suppressed entanglement spreading and tunable particle multiplicities, which are seen to be signatures of confinement and string breaking. Particle multiplicities typically grow monotonically with time and system size and depend sensitively on simulator detuning and interaction scales. These results establish the ladder geometry as a viable near-term analog quantum simulator of string fragmentation, and motivate hybrid workflows in which quantum devices contribute nonperturbative real-time dynamics to event generation.

quant-ph↗