Efficient and tunable qubit unidirectional routers and spin-wave diodes play an important role in classical and quantum information processing domains. Here we reveal that multilevel neutral cold atoms can mediate both dissipative and coherent couplings. Interestingly, we investigate and practically implement this paradigm in experiments, successfully synthesizing a system with dual functionality as both a photonic qubit unidirectional router and a spin-wave diode. By manipulating the helicity of the field, we can effectively balance the coherent coupling and the dissipative channel, thereby ensuring the unidirectional transfer of photonic qubits. The qubit fidelity exceeds $(97.49\pm 0.39)\mathrm{\%}$, and the isolation ratio reaches $16.8\pm 0.11$ dB, while the insertion loss is lower than 0.36 dB. Furthermore, we show that the spin-wave diode can effectively achieve unidirectional information transfer by our appropriately setting the coherent-coupling parameters. Our work not only provides ideas for the design of extensive components in quantum network but also opens up possibilities for non-Hermitian quantum physics, complex quantum networks, and unidirectional quantum information transfer.

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• Light-matter interaction
• Magnons
• Non-reciprocal propagation
• Photonics
• Quantum information with atoms & light
• Atomic ensemble
• Non-Hermitian systems
• Qubits