We investigate the schemes of quantum network teleportation for quantum
information distribution and concentration which are essential in quantum cloud
computation and quantum internet. In those schemes, the cloud can send
simultaneously identical unknown quantum states to clients located in different
places by a network like teleportation with a prior shared multipartite
entangled state resource. The cloud first perform the quantum operation, each
client can recover their quantum state locally by using the classical
information announced by the cloud about the measurement result. The number of
clients can be beyond the number of identical quantum states intentionally
being sent, this quantum network teleportation can make sure that the retrieved
quantum state is optimal. Furthermore, we present a scheme to realize its
reverse process, which concentrates the states from the clients to reconstruct
the original state of the cloud. These schemes facilitate the quantum
information distribution and concentration in quantum networks in the framework
of quantum cloud computation. Potential applications in time synchronization
are discussed.Comment: 7 pages, 1 figur
