Realization Of The Quantum Algorithm And Its Simulation Of The Nmr Experiment

In the first part of this article, the basic content and the new development of quantum information theory are systematically introduced, and the characteristic and the superiority of quantum computer are discussed in detail. Because of massive quantum superposition and entanglement, quantum computer can solve many problems more efficiently. TSP and knapsack problems are typical NPC problems.Their computing complexity is 0(2n) steps. This paper gives respectively quantummechanical algorithms to solve TSP and knapsack problems. The algorithm for TSP uses the principles of the Graver's algorithm, and A Polynomial-Time Quantum Algorithms for the knapsack problem is proposed in mis paper, hi which the method of divide is adopted, it divides the vector space into two subspaces until the solution isfound. As a result, the desired solution can be obtained in O(cn) quantum time forthe n-element knapsack problem.In the second part of this article, the simulation approaches are described to realize the functioning of the various quantum logic gates, Graver's algorithm and the shor's Algorithm. These simulation approaches use the nuclear magnetic resonance (NMR) experiment technology. NMR can rotate the spins through radio frequency (RF) electromagnetic pulses. By tuning the frequency of the RF-field to the precession frequency of a particular spin, the power of the applied pulse controls how much the spin will rotate. The axis of the rotation is determined by the direction of the applied RF-field. By selecting the appropriate RF pulses, arbitrary single-spin rotation can be carried out. In other words, using RF pulses we can perform any single-qubit operation. Communication between the qubits is accomplished through the spin-spin interaction in model.