Lead commutation for quantum switching

Quantum network will play an important role in the field of quantum information and quantum communication. We propose a new quantum network scheme where a lead commutation is used to reduce the switching time for transferring quantum packets containing unknown quantum states. The switching circuits with lead commutation are specifically presented for the two cases with one and multi-switching nodes. With the help of lead commutation, one can directly route a quantum packet to its corresponding output port and reduce the communication time in quantum networks.