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arXiv · 1112.3465

Storage of classical information in quantum spins

F. Delgado·J. Fernández-Rossier
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Abstract

Digital magnetic recording is based on the storage of a bit of information in the orientation of a magnetic system with two stable ground states. Here we address two fundamental problems that arise when this is done on a quantized spin: quantum spin tunneling and back-action of the readout process. We show that fundamental differences exist between integer and semi-integer spins when it comes to both, read and record classical information in a quantized spin. Our findings imply fundamental limits to the miniaturization of magnetic bits and are relevant to recent experiments where spin polarized scanning tunneling microscope reads and records a classical bit in the spin orientation of a single magnetic atom.

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F. Delgado, J. Fernández-Rossier. 2011-12-15. Storage of classical information in quantum spins. https://doi.org/10.1103/physrevlett.108.196602

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