Quantum Information Processing Via Mach-Zehnder Interferometer

Quantum information science is a new inter-discipline which includes quantum computation and quantum communication in general. Quantum secret sharing, quantum dense coding, quantum key distribution, (remote) generation of quantum state and quantum teleportation are all belong to the quantum communication. Quantum teleportation, an important application of entanglement, has got remarkable progress both experimentally and theoretically. The so called quantum teleportation is a process to transmit an unknown quantum state from a sender (Alice) to a receiver (Bob) through the quantum channel, i.e., entanglement between the two parties, with the help of classical communication. After the teleportation process, the particles which carry the original unknown quantum state are still left at the sender's side. Considering the experimental difficult in realizing the joint measurement, which is commonly adopted in previous schemes, we propose here some quantum teleportation schemes via the linear optical elements with particular focus on Mach-Zehnder interferometer. The mainly results are included as following:1. Generation of quantum channel, that is, quantum entangled state. This scheme can convert the joint measurement into the product of separate single-qubit measurements via Mach-Zehnder interferometer, which greatly reduces the experimental implementation difficulty.2. Linear optics scheme of quantum teleportation. These schemes avoid the prior distribution of quantum channel. We realize the generation of quantum channel and the teleportation in one setup and one process, then generalize the scheme to the case of bipartite arbitrary ionic state and multi-ionic GHZ state.3. Linear optics scheme for controlled teleportation. We introduce a third-party control based on our previous schemes and realize the multi-participant quantum teleportation via linear optical elements.