Research Of Quantum Gate Teleportation And Its Fidelity

Current quantum teleportation usually refers to teleportation of quantum state of a qubit,which has already been realized experimentally.However recently an experiment team from Yale University successfully realized deterministic teleportation of a quantum gate between two logical qubits,which could be crucial for building modular quantum computer.The main objective of quantum gate teleportation is to perform a two-qubit gate operation on two data qubits in two independent modules respectively without direct interaction between these two modules.Actually the process of quantum gate teleportation is similar to state teleportation,and they both rely on the quantum communication channel created by entanglement states.Using corresponding quantum circuit and follow these 4 steps:(1)entangle two communication qubits(2)local operations performed within each module(3)perform measurements on the communication qubits(4)classical communication and feedforward operations,we can realize deterministic teleportation of a CNOT gate between two data qubits.And we can extend gate teleportation even further:we can realize Controlled-G gate teleportation if G2=1 by modifying the quantum circuit.Based on the above I established a mathematical model to study time evolution of the quantum system under noise like magnetic field or other decoherence circumstance.I also theoretically calculate the fidelity between final state and ideal state,and hopefully select a better Bell state as entanglement state.