Quantum Computation And Information Processing Based On NMR Technique

Quantum information Processing (QIP) is a new field, which emerged when quantum mechanics was applied to information science. In recent years, Some miraculous properties of quantum mechanics such as entanglement, superposition, no cloning and so on have been used in computation science and information science. These applications have surmounted the classical limitations and accelerated the development of computation and information transmission sciences. Now, the QIP is becoming a hot topic of scientific research. It is also one of the most promising subjects in quantum physics. Scientists are working hard to set up some practical quantum computers. In the experimental projects of quantum computation, the technique of nuclear Magnetic Resonance (NMR) is in great progress! Indeed, for small quantum computer, liquid state NMR techniques are used ahead of the others in competition. Therefore, the investition of the NMR quantum computing is chosen as the subject of my dissertation. The major work is as follows:1. Using the pulse sequences of the basic logical gates, some complex logical gates of three qubits are constructed, such as Controlled - controlled phaseshift gate. The Grover's quantum algorithm of three qubit in the simulator of NMR is realized.2. Based on the effective pure states, the effective EPR states are created. In NMR experiment, the property of EPR state is demonstrated, which is quantum correlation without classical correspondence. So we can display the quantum effects on NMR quantum computer.3. Taking advantage of swap transformation and quantum dense coding, we can transfer information between two particles which have no direct interaction on each other.4. We analysis some difficulties in the scaling of liquid state NMR quantum computer and provide some possible solvable items.