String order melting of spin-1 particle chains in superconducting transmons using optimal control

TL;DR

This paper demonstrates the use of optimal control pulses to simulate and observe the melting of string order in spin-1 chains within superconducting transmon qubits, showing promising results for high-fidelity quantum simulations.

Contribution

It introduces a method for designing optimal control pulses to simulate non-equilibrium topological state dynamics in superconducting qubits, advancing quantum simulation capabilities.

Findings

Successful simulation of string order melting with low infidelity

Feasibility of high-fidelity quantum simulations on current hardware

Efficient pulse optimization for complex many-body dynamics

Abstract

Utilizing optimal control to simulate a model Hamiltonian is an emerging strategy that leverages the intrinsic physics of a device with digital quantum simulation methods. Here we evaluate optimal control for probing the non-equilibrium properties of symmetry-protected topological (SPT) states simulated with superconducting hardware. Assuming a tunable transmon architecture, we cast evolution of these SPT states as a series of one- and two-site pulse optimization problems that are solved in the presence of leakage constraints. From the generated pulses, we numerical simulate time-dependent melting of the perturbed SPT string order across a six-site model with an average state infidelity of $10^{-3}$. The feasibility of these pulses as well as their efficient application indicate that high-fidelity simulations of string-order melting are within reach of current quantum computing systems.