Entanglement preservation in non-Markovian open quantum systems*

Dissipation is critical to the function of noisy intermediate-scale quantum processors as it allows for initialization, error correction and other methods of control. Dissipation is also, unfortunately, the source of most errors in these processors. For theoretical simplicity, this dissipation is typically treated as Markovian, yet we know that on some level memory effects of the dissipative bath will contribute to the quantum dynamics. This leads to correlated errors that prevent straightforward approaches to error correction. However, several theoretical studies have identified ways in which non-Markovian dissipation can also provide advantages to quantum processors, particularly in the preservation of entanglement. In this work, we design a multi-qubit superconducting processor consisting of two coupled qubits interacting with a small quantum bath to realize non-Markovian dynamics. By examining the evolution of entangled states of the qubits in the presence of memory induced by the bath, we investigate the parameters required to observe a transition from Markovian to non-Markovian regime and the role of non-Markovianity in the preservation of the entangled states.