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arXiv · 1703.09419

Three-atom magnets with strong substrate coupling: a gateway towards non-collinear spin processing

J. Hermenau·J. Ibañez-Azpiroz·Chr. Hübner·A. Sonntag·B. Baxevanis·K. T. Ton·M. Steinbrecher·A. A. Khajetoorians·M. dos Santos Dias·S. Blügel·R. Wiesendanger·S. Lounis·J. Wiebe
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Abstract

A cluster composed of a few magnetic atoms assembled on the surface of a nonmagnetic substrate is one suitable realization of a bit for future concepts of spin-based information technology. The prevalent approach to achieve magnetic stability of the bit is decoupling the cluster spin from substrate conduction electrons in order to suppress spin-flips destabilizing the bit. However, this route entails less flexibility in tailoring the coupling between the bits which is ultimately needed for spin-processing. Here, we show using a spin-resolved scanning tunneling microscope, that we can write, read, and store spin information for hours in clusters of only three atoms strongly coupled to a substrate featuring a cloud of non-collinearly polarized host atoms, a so called non-collinear giant moment cluster (GMC). The GMC can be driven into a Kondo screened state by simply moving one of its atoms to a different site. Owing to the exceptional atomic tunability of the non-collinear substrate mediated Dzyaloshinskii-Moriya interaction, novel concepts of spin-based information technology get within reach, as we demonstrate by a logical scheme for a four-bit register.

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J. Hermenau, J. Ibañez-Azpiroz, Chr. Hübner, A. Sonntag, B. Baxevanis, K. T. Ton, M. Steinbrecher, A. A. Khajetoorians, M. dos Santos Dias, S. Blügel, R. Wiesendanger, S. Lounis, J. Wiebe. 2017-03-28. Three-atom magnets with strong substrate coupling: a gateway towards non-collinear spin processing. https://arxiv.org/abs/1703.09419

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