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arXiv · 2211.14205

Certifying entanglement of spins on surfaces using ESR-STM

Y. del Castillo·J. Fernández-Rossier
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Abstract

We propose a protocol to certify the presence of entanglement in artificial on-surface atomic and molecular spin arrays using electron spin resonance carried by scanning tunnel microscopes (ESR-STM). We first generalize the theorem that relates global spin susceptibility as an entanglement witness to the case of anisotropic Zeeman interactions, relevant for surfaces. We then propose a method to measure the spin susceptibilities of surface-spin arrays combining ESR-STM with atomic manipulation. Our calculations show that entanglement can be certified in antiferromagnetically coupled spin dimers and trimers with state of the art ESR-STM magnetometry.

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Y. del Castillo, J. Fernández-Rossier. 2022-11-25. Certifying entanglement of spins on surfaces using ESR-STM. https://arxiv.org/abs/2211.14205

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