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Title: Scanning tunnelling spectroscopy as a probe of multi-Q magnetic states of itinerant magnets

Abstract

The combination of electronic correlations and Fermi surfaces with multiple nesting vectors can lead to the appearance of complex multi-Q magnetic ground states, hosting unusual states such as chiral density waves and quantum Hall insulators. Distinguishing single-Q and multi-Q magnetic phases is however a notoriously difficult experimental problem. Here we propose theoretically that the local density of states (LDOS) near a magnetic impurity, whose orientation may be controlled by an external magnetic field, can be used to map out the detailed magnetic configuration of an itinerant system and distinguish unambiguously between single-Q and multi-Q phases. We demonstrate this concept by computing and contrasting the LDOS near a magnetic impurity embedded in three different magnetic ground states relevant to iron-based superconductors—one single-Q and two double-Q phases. Our results open a promising avenue to investigate the complex magnetic configurations in itinerant systems via standard scanning tunnelling spectroscopy, without requiring spin-resolved capability.

Authors:
 [1];  [2];  [3]; ORCiD logo [1]
  1. Univ. of Copenhagen (Denmark). The Niels Bohr Inst.
  2. Ruhr Univ., Bochum (Germany). Inst. for Theoretical Physics; Kazan Federal Univ. (Russian Federation). Inst. of Physics
  3. Univ. of Minnesota, Minneapolis, MN (United States). School of Physics and Astronomy
Publication Date:
Research Org.:
Univ. of Minnesota, Minneapolis, MN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1347385
Grant/Contract Number:
SC0012336
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 36 MATERIALS SCIENCE; magnetic properties and materials; surfaces, interfaces and thin films

Citation Formats

Gastiasoro, Maria N., Eremin, Ilya, Fernandes, Rafael M., and Andersen, Brian M. Scanning tunnelling spectroscopy as a probe of multi-Q magnetic states of itinerant magnets. United States: N. p., 2017. Web. doi:10.1038/ncomms14317.
Gastiasoro, Maria N., Eremin, Ilya, Fernandes, Rafael M., & Andersen, Brian M. Scanning tunnelling spectroscopy as a probe of multi-Q magnetic states of itinerant magnets. United States. doi:10.1038/ncomms14317.
Gastiasoro, Maria N., Eremin, Ilya, Fernandes, Rafael M., and Andersen, Brian M. Wed . "Scanning tunnelling spectroscopy as a probe of multi-Q magnetic states of itinerant magnets". United States. doi:10.1038/ncomms14317. https://www.osti.gov/servlets/purl/1347385.
@article{osti_1347385,
title = {Scanning tunnelling spectroscopy as a probe of multi-Q magnetic states of itinerant magnets},
author = {Gastiasoro, Maria N. and Eremin, Ilya and Fernandes, Rafael M. and Andersen, Brian M.},
abstractNote = {The combination of electronic correlations and Fermi surfaces with multiple nesting vectors can lead to the appearance of complex multi-Q magnetic ground states, hosting unusual states such as chiral density waves and quantum Hall insulators. Distinguishing single-Q and multi-Q magnetic phases is however a notoriously difficult experimental problem. Here we propose theoretically that the local density of states (LDOS) near a magnetic impurity, whose orientation may be controlled by an external magnetic field, can be used to map out the detailed magnetic configuration of an itinerant system and distinguish unambiguously between single-Q and multi-Q phases. We demonstrate this concept by computing and contrasting the LDOS near a magnetic impurity embedded in three different magnetic ground states relevant to iron-based superconductors—one single-Q and two double-Q phases. Our results open a promising avenue to investigate the complex magnetic configurations in itinerant systems via standard scanning tunnelling spectroscopy, without requiring spin-resolved capability.},
doi = {10.1038/ncomms14317},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = {Wed Feb 08 00:00:00 EST 2017},
month = {Wed Feb 08 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 2works
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