With current technologies, it seems to be very difficult to im- plement quantum computers with many qubits. It is therefore of impor- tance to simulate quantum algorithms and circuits on the existing com- puters. However, for a large-size problem, the simulation often requires more computational power than is available from sequential processing. Therefore, simulation methods for parallel processors are required.
We have developed a general-purpose simulator for quantum algorithms/ circuits on the parallel computer (Sun Enterprise4500). It can simulate algorithms/circuits with up-to 30 qubits. In order to test efficiency of our proposed methods, we have simulated Shor’s factorization algorithm and Grover’s database search, and we have analyzed robustness of the corresponding quantum circuits in the presence of both decoherence and operational errors. The corresponding results, statistics and analyses are presented in this paper.