Characterization of complex quantum dynamics with a scalable NMR information processor

Full text: We will present experimental results showing the measurement of fidelity decay using a nuclear magnetic resonance quantum computer. Using a scalable circuit we were able to implement a coarse-grained characterization of simulated complex quantum dynamics. The results match the expected theoretical decay rate and show a clear difference between regular and chaotic behaviour. Moreover, the results demonstrate a scalable way for extracting information from a large system using only on quantum bit of information. (author)