Complexity of controlling quantum many-body dynamics

Printer-friendly versionSend by emailPDF version

T. Caneva, A. Silva, R. Fazio, S. Lloyd, T. Calarco, and S. Montangero


Phys. Rev. A 89, 042322 (2014)

We demonstrate that arbitrary time evolutions of many-body quantum systems can be reversed even in cases when only part of the Hamiltonian can be controlled. The reversed dynamics obtained via optimal control—contrary to standard time-reversal procedures—is extremely robust to external sources of noise. We provide a lower bound on the control complexity of a many-body quantum dynamics in terms of the dimension of the manifold supporting it, elucidating the role played by integrability in this context.