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arXiv · 1602.09068

Clocked single-spin source based on a spin-split superconductor

Niklas Dittmann·Janine Splettstoesser·Francesco Giazotto
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Abstract

We propose an accurate clocked single-spin source for ac-spintronic applications. Our device consists of a superconducting island covered by a ferromagnetic insulator layer through which it is coupled to superconducting leads. Single-particle transfer relies on the energy gaps and the island's charging energy, and is enabled by a bias and a time-periodic gate voltage. Accurate spin transfer is achieved by the ferromagnetic insulator layer which polarizes the island, provides spin-selective tunneling barriers and improves the precision by suppressing Andreev reflection. We analyze realistic material combinations and experimental requirements which allow for a clocked spin current in the MHz regime.

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Niklas Dittmann, Janine Splettstoesser, Francesco Giazotto. 2016-09-23. Clocked single-spin source based on a spin-split superconductor. https://doi.org/10.1088/1367-2630%2F18%2F8%2F083019

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