2 research outputs found
Simulation of static and random errors on Grover's search algorithm implemented in a Ising nuclear spin chain quantum computer with few qubits
We consider Grover's search algorithm on a model quantum computer implemented
on a chain of four or five nuclear spins with first and second neighbour Ising
interactions. Noise is introduced into the system in terms of random
fluctuations of the external fields. By averaging over many repetitions of the
algorithm, the output state becomes effectively a mixed state. We study its
overlap with the nominal output state of the algorithm, which is called
fidelity. We find either an exponential or a Gaussian decay for the fidelity as
a function of the strength of the noise, depending on the type of noise (static
or random) and whether error supression is applied (the 2pi k-method) or not.Comment: 18 pages, 8 figures, extensive revision with new figure
Noise effects in the quantum search algorithm from the computational complexity point of view
We analyse the resilience of the quantum search algorithm in the presence of
quantum noise modelled as trace preserving completely positive maps. We study
the influence of noise on computational complexity of the quantum search
algorithm. We show that only for small amounts of noise the quantum search
algorithm is still more efficient than any classical algorithm.Comment: 7 pages, 2 figure