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Title: Single-atom gating and magnetic interactions in quantum corrals

Abstract

Single-atom gating, achieved by manipulation of adatoms on a surface, has been shown in experiments to allow precise control over superposition of electronic states in quantum corrals. Using a Green's function approach, we demonstrate theoretically that such atom gating can also be used to control the coupling between magnetic degrees of freedom in these systems. Atomic gating enables control not only on the direct interaction between magnetic adatoms, but also over superpositions of many-body states which can then control long distance interactions. We illustrate this effect by considering the competition between direct exchange between magnetic impurities and the Kondo screening mediated by the host electrons, and how this is affected by gating. These results suggest that both magnetic and nonmagnetic single-atom gating may be used to investigate magnetic impurity systems with tailored interactions, and may allow the control of entanglement of different spin states.

Authors:
; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
National Science Foundation (NSF)
OSTI Identifier:
1372667
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 95; Journal Issue: 16
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Ngo, Anh T., Kim, Eugene H., and Ulloa, Sergio E.. Single-atom gating and magnetic interactions in quantum corrals. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.95.161407.
Ngo, Anh T., Kim, Eugene H., & Ulloa, Sergio E.. Single-atom gating and magnetic interactions in quantum corrals. United States. doi:10.1103/PhysRevB.95.161407.
Ngo, Anh T., Kim, Eugene H., and Ulloa, Sergio E.. Sat . "Single-atom gating and magnetic interactions in quantum corrals". United States. doi:10.1103/PhysRevB.95.161407.
@article{osti_1372667,
title = {Single-atom gating and magnetic interactions in quantum corrals},
author = {Ngo, Anh T. and Kim, Eugene H. and Ulloa, Sergio E.},
abstractNote = {Single-atom gating, achieved by manipulation of adatoms on a surface, has been shown in experiments to allow precise control over superposition of electronic states in quantum corrals. Using a Green's function approach, we demonstrate theoretically that such atom gating can also be used to control the coupling between magnetic degrees of freedom in these systems. Atomic gating enables control not only on the direct interaction between magnetic adatoms, but also over superpositions of many-body states which can then control long distance interactions. We illustrate this effect by considering the competition between direct exchange between magnetic impurities and the Kondo screening mediated by the host electrons, and how this is affected by gating. These results suggest that both magnetic and nonmagnetic single-atom gating may be used to investigate magnetic impurity systems with tailored interactions, and may allow the control of entanglement of different spin states.},
doi = {10.1103/PhysRevB.95.161407},
journal = {Physical Review B},
number = 16,
volume = 95,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
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