Investigations on resource-limited quantum control through NMR pulses

Abstract

Universal high fidelity coherent control over large Hilbert spaces is essential for quantum information processing to become a useful tool in science, engineering, communications and computation. The development of methods for coherent control are however still in their infancy. In particular, very little is known about the efficiency of quantum control subject to limitations in resources such as drive power, drive bandwidth and system decoherence. Here we report the results of numerical simulations to investigate the influence of limited resources. We introduce the curvature of fidelity as a measure of robustness. We apply these ideas to strongly modulating NMR pulse sequences and study the effects of increasing resources on the fidelity and curvature.