Topological edge state transfer via topological adiabatic passage

TL;DR

This paper demonstrates topological adiabatic passage for quantum state transfer in superconducting qubit chains, utilizing topological edge states and Landau-Zener models to achieve robust transfer of quantum states.

Contribution

It introduces a method to transfer quantum states via topological edge states in superconducting qubits, linking topological adiabatic passage to Landau-Zener models for the first time.

Findings

Successful transfer of spin-up states along topological qubit chains.

Reduction of the system to a two-state Landau-Zener model.

Extension of the method to transfer two-qubit Bell states.

Abstract

The study of quantum state transfer has led to a variety of research efforts utilizing quantum simulators. By exploiting the tunability of the qubit frequency and qubit-qubit coupling, a superconducting qubit chain can simulate various topological band models. In our study, we demonstrate that a spin-up state can be transported along a topological qubit chain by modulating the coupling strengths and the qubit frequencies. We show that the Hilbert space of the qubit chain can be restricted to the subspace of two edge states in this process, while the Hamiltonian degenerates into a two-state Landau-Zener (LZ) model. Furthermore, we prove that the state transfer process in this topological qubit chain is equivalent to the topological adiabatic passage of the LZ model. With this analysis, we generalize the state transfer approach from single-qubit Fock states to two-qubit Bell states.