Effect of varying the position of the ancilla qubit and the coupling constants in the simulation of Grover's quantum search algorithm


We simulate Grover's algorithm in an Ising spin chain quantum computer with spatially-dependent coupling constant. The interaction to the nearest and second-nearest neighbor of the spins is considered. The behavior of the fidelity as a function of the number of Grover iteration during the algorithm is determined. For a fixed location of the ancilla qubit, the overall fidelity decreases as we increase the size of the database. Also, as we vary the coupling constant per neighbor, we obtain a high fidelity for a given number of iteration. The simulation of the algorithm using a classical computer system restricts the size of the database that gives a high fidelity result.