[Colloquium] Novel quantum dynamics with superconducting qubits

Speaker: Pedram Roushan, Google Quantum AI, Santa Barbara

Title: Novel quantum dynamics with superconducting qubits

Abstract: In recent years, superconducting qubits have emerged as a leading platform for quantum simulation of non-equilibrium dynamics on Noisy Intermediate-Scale Quantum (NISQ) processors. I will discuss some of our recent work in this area. Motivated by questions in high-energy physics, we directly image the dynamics of charges and strings in (2+1)-dimensional lattice gauge theories [1], revealing two distinct regimes within the confining phase: a weak-confinement regime where the string exhibits strong transverse fluctuations, and a strong-confinement regime where these fluctuations are significantly suppressed. Turning to condensed matter physics, in another study [2] we observe a novel form of localization in quantum many-body systems in one and two dimensions. The dynamics exhibit a striking absence of energy diffusion even when the evolution operator is disorder-free and the initial states are fully translationally invariant. These results demonstrate that NISQ processors, even short of fault-tolerant quantum computers, are powerful tools for probing non-equilibrium quantum phenomena and advancing our understanding of complex quantum dynamics.

[1] Cochran et al., Nature 642, 315–320 (2025)

[2] Gyawali  et al., arxiv.org/abs/2410.06557