Observation of genuine 2+1D string dynamics in a U(1) lattice gauge theory with a tunable plaquette term on a trapped-ion quantum computer · arXivDesk
2604.07436Apr 8, 2026$12+13$ pages, $4+12$ figures, $0+1$ table. See parallel submission by K. Xu et al., "Observation of glueball excitations and string breaking in a $2+1$D $\mathbb{Z}_2$ lattice gauge theory on a trapped-ion quantum computer''
Observation of genuine 2+1D string dynamics in a U(1) lattice gauge theory with a tunable plaquette term on a trapped-ion quantum computer
Rohan Joshi, Yizhuo Tian, Kevin Hemery, N. S. Srivatsa, Jesse J. Osborne, Henrik Dreyer, Enrico Rinaldi, Jad C. Halimeh
Quantum simulations of high-energy physics in 2+1D can probe dynamical phenomena nonexistent in one spatial dimension and access regimes that are challenging for existing classical simulation methods. For string dynamics -- relevant to hadronization -- a plaquette term is required to realize genuine 2+1D behavior, as it endows the gauge field with dynamics and enables the propagation of photon-like excitations. Here, we realize a U(1) quantum link model of quantum electrodynamics in two spatial dimensions with a tunable plaquette term on a Quantinuum System Model H2 quantum computer. We implement, to our knowledge, the largest quantum simulation of string-breaking dynamics reported to date, on a 5×4
Nearby in the stack
matter-site square lattice using
51
qubits. The simulation uses a shallow circuit design with a two-qubit gate depth of
28
per Trotter step and up to
1540
entangling gates. Starting from far-from-equilibrium string configurations, we measure the probability for the string to propagate within the lattice plane and find signatures of genuine
2+1
D dynamics only when the plaquette term is present. In a resonant regime, we observe the annihilation of string segments accompanied by the production of electron--positron pairs that screen them. We further find that, only with a nonzero plaquette term, matter creation extends across the lattice plane rather than remaining confined to the initial string path. These results experimentally realize string breaking and demonstrate the emergence of dynamical gauge fields in two spatial dimensions, establishing a route to photon-like propagation in programmable quantum simulators of gauge theories.