We are interested in fundamental limits to computation imposed by physical constraints. In particular, the physical laws of motion constrain the speed at which a computer can transition between well-defined states. Certain time bounds are known, but these are not tight bounds. For computation, we also need to consider bounds in the presence of control functions. Here, we use a numerical search approach to discover specific optimal control schemes. We present results for two coupled spins controlled in two scenarios: (i) a single control field influencing each spin separately; (ii) two orthogonal control fields influencing each spin.
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@inproceedings(SS-UCNC13-num, author = "Benjamin Russell and Susan Stepney", title = "Numerical Analysis of Quantum Speed Limits: controlled quantum spin chain systems with constrained control functions", pages = "209-219", crossref = "UCNC13" ) @proceedings(UCNC13, title = "Unconventional Computation and Natural Computation 2013, Milan, Italy, July 2013", booktitle = "Unconventional Computation and Natural Computation 2013, Milan, Italy, July 2013", series = "LNCS", volume = 7956, publisher = "Springer", year = 2013 )