Abstract In a local quantum network, multi-qubits in various entangled states might be distributed in different remote nodes due to some peculiar demands. In this paper we consider a seven-qubit entangled state in a given qubit distribution among three participants and study its capacity in quantum teleportation (QT). To be specific, we put forward three controlled QT schemes utilizing the state. In each scheme QT can be deterministically and bidirectionally realized between two participants with another as the controller.
Quantum entanglement plays an irreplaceable role in various remote quantum information processing tasks. Here we present protocols for generating deterministic and heralded
N-qubit entangled states across multiple network nodes. By utilizing a pre-shared maximally entangled state and single-qubit operations within an indefinite causal order framework, the multi-qubit entangled state between distant parties can be generated deterministically. The complex entangled state measurements and multiple pre-shared entangled states, are essential in conventional entanglement swapping technique, but are not required in our approach. This greatly reduces the complexity of the quantum circuit and makes it more experimentally feasible. Furthermore, we develop optical architectures to implement these protocols by encoding qubits in polarization degree of freedom. The results indicate that our protocols significantly improve the efficiency of long-distance entanglement generation and provide a practical framework for establishing large-scale quantum networks.