Abstract
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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Russell, B., Stepney, S. (2013). Numerical Analysis of Quantum Speed Limits: Controlled Quantum Spin Chain Systems with Constrained Control Functions. In: Mauri, G., Dennunzio, A., Manzoni, L., Porreca, A.E. (eds) Unconventional Computation and Natural Computation. UCNC 2013. Lecture Notes in Computer Science, vol 7956. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-39074-6_20
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DOI: https://doi.org/10.1007/978-3-642-39074-6_20
Publisher Name: Springer, Berlin, Heidelberg
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