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arXiv · 1308.2882

Towards experimental tests and applications of Lieb-Robinson bounds

Kolja Them
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Abstract

Spin-polarized scanning tunneling microscopy is identified as a suitable experimental technique to investigate the quantitative quality of Lieb-Robinson bounds on the signal velocity. The latest, most general bound is simplified and it is shown that there is a discrepancy by a factor of approximately 4 between the corresponding limit speed and some estimated exact velocities in atomic spin chains. The observed discrepancy facilitates conclusions for a further mathematical improvement of Lieb-Robinson bounds. The real signal propagation can be modified with several experimental parameters from which the bounds are independent. This enables the application of Lieb-Robinson bounds as upper limits on the enhancement of the real signal speed for information transport in spintronic devices.

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Kolja Them. 2013-12-09. Towards experimental tests and applications of Lieb-Robinson bounds. https://doi.org/10.1103/physreva.89.022126

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