Robust quantum state transfer with topologically protected nodes

Robust quantum state transfer (QST) is the foundation for information exchange among nodes in quantum networks. In this paper, we propose a robust QST protocol that utilizes topological edge modes in the qubit chains to encode (decode) quantum states (flying qubits). By employing qubits with tunable couplings, we construct Su-Schrieffer-Heeger (SSH) chains as the nodes of a quantum network. The end qubit of each SSH chain is dissipatively coupled to a chiral waveguide, and the dissipative strength is a constant. We refer to the SSH chain with a dissipation channel at the end qubit as the non -Hermitian SSH chain. Comparing the symmetry and energy spectra of the non -Hermitian SSH chain with those of the SSH chain, our analysis reveals that the dissipative dynamics of the topological edge state in the non -Hermitian SSH chain are governed by its imaginary spectra. The edge mode with the imaginary spectrum can be used to encode (decode) quantum states (flying qubits), thereby enabling robust QST between two remote mirrored non -Hermitian SSH chains. Our numerical simulations demonstrate that high-fidelity QST can be achieved even in the presence of coupling errors. Furthermore, we extend our analysis to consider QST in imperfect chiral waveguides, providing insights into the robustness of our protocol under realistic conditions. Our discussion is applicable to various quantum platforms and holds significant implications for constructing large-scale quantum networks.