Error-Mitigated Simulation of Quantum Many-Body Scars on Quantum Computers with Pulse-Level Control

Understand

Quantum many-body scars are an intriguing dynamical regime in which quantum systems exhibit coherent dynamics and long-range correlations when prepared in certain initial states.

• We use this combination of coherence and many-body correlations to benchmark the performance of present-day quantum computing devices by using them to simulate the dynamics of an antiferromagnetic initial state in mixed-field Ising chains of up to 19 sites.
• In addition to calculating the dynamics of local observables, we also calculate the Loschmidt echo and a nontrivial connected correlation function that witnesses long-range many-body correlations in the scarred dynamics.
• We find coherent dynamics to persist over up to 40 Trotter steps even in the presence of various sources of error.