Energy gap of topological surface states in proximity to a magnetic insulator

Jiashu Wang; Tianyi Wang; Mykhaylo Ozerov; Zhan Zhang; Joaquin Bermejo-Ortiz; Seul Ki Bac; Hoai Trinh; Maksym Zhukovskyi; Tatyana Orlova; Haile Ambaye; Jong Keum; Louis Anne de Vaulchier; Yves Guldner; Dmitry Smirnov; Valeria Lauter; Xinyu Liu; Badih A. Assaf

doi:10.1038/s42005-023-01327-5

Energy gap of topological surface states in proximity to a magnetic insulator

Jiashu Wang, Tianyi Wang, Mykhaylo Ozerov, Zhan Zhang, Joaquin Bermejo-Ortiz, Seul Ki Bac, Hoai Trinh, Maksym Zhukovskyi, Tatyana Orlova, Haile Ambaye, Jong Keum, Louis Anne de Vaulchier, Yves Guldner, Dmitry Smirnov, Valeria Lauter, Xinyu Liu, Badih A. Assaf

Research output: Contribution to journal › Article › peer-review

2 Scopus citations

Abstract

Topological surface-states can acquire an energy gap when time-reversal symmetry is broken by interfacing with a magnetic insulator. This gap has yet to be measured. Such topological-magnetic insulator heterostructures can host a quantized anomalous Hall effect and can allow the control of the magnetic state of the insulator in a spintronic device. In this work, we observe the energy gap of topological surface-states in proximity to a magnetic insulator using magnetooptical Landau level spectroscopy. We measure Pb_1-xSn_xSe–EuSe heterostructures grown by molecular beam epitaxy exhibiting a record mobility and low Fermi energy. Through temperature dependent measurements and theoretical calculations, we show this gap is likely due to quantum confinement and conclude that the magnetic proximity effect is weak in this system. This weakness is disadvantageous for the realization of the quantum anomalous Hall effect, but favorable for spintronic devices which require the preservation of spin-momentum locking at the Fermi level.

Original language	English
Article number	200
Journal	Communications Physics
Volume	6
Issue number	1
DOIs	https://doi.org/10.1038/s42005-023-01327-5
State	Published - Dec 2023

Funding

Work supported by NSF-DMR-1905277. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreements No. DMR-1644779, DMR-2128556, and the State of Florida. This research used resources at the Spallation Neutron Source, a Department of Energy Office of Science User Facility operated by the Oak Ridge National Laboratory. XRR measurements were conducted at the Center for Nanophase Materials Sciences (CNMS), which is a DOE Office of Science User Facility. We also acknowledge support from the Notre Dame Integrated Imaging Facility. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility, operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02–06CH11357. Work supported by NSF-DMR-1905277. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreements No. DMR-1644779, DMR-2128556, and the State of Florida. This research used resources at the Spallation Neutron Source, a Department of Energy Office of Science User Facility operated by the Oak Ridge National Laboratory. XRR measurements were conducted at the Center for Nanophase Materials Sciences (CNMS), which is a DOE Office of Science User Facility. We also acknowledge support from the Notre Dame Integrated Imaging Facility. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility, operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02–06CH11357.

Funders	Funder number
NSF-DMR-1905277
National Science Foundation	DMR-1644779, DMR-2128556
U.S. Department of Energy
Office of Science
Argonne National Laboratory	DE-AC02–06CH11357
Oak Ridge National Laboratory
Notre Dame Integrated Imaging Facility, University of Notre Dame
State of Florida

Access to Document

10.1038/s42005-023-01327-5

Cite this

Wang, J., Wang, T., Ozerov, M., Zhang, Z., Bermejo-Ortiz, J., Bac, S. K., Trinh, H., Zhukovskyi, M., Orlova, T., Ambaye, H., Keum, J., de Vaulchier, L. A., Guldner, Y., Smirnov, D., Lauter, V., Liu, X., & Assaf, B. A. (2023). Energy gap of topological surface states in proximity to a magnetic insulator. Communications Physics, 6(1), Article 200. https://doi.org/10.1038/s42005-023-01327-5

@article{0a72a1c6efbe40c2baeadb317153cff8,

title = "Energy gap of topological surface states in proximity to a magnetic insulator",

abstract = "Topological surface-states can acquire an energy gap when time-reversal symmetry is broken by interfacing with a magnetic insulator. This gap has yet to be measured. Such topological-magnetic insulator heterostructures can host a quantized anomalous Hall effect and can allow the control of the magnetic state of the insulator in a spintronic device. In this work, we observe the energy gap of topological surface-states in proximity to a magnetic insulator using magnetooptical Landau level spectroscopy. We measure Pb1-xSnxSe–EuSe heterostructures grown by molecular beam epitaxy exhibiting a record mobility and low Fermi energy. Through temperature dependent measurements and theoretical calculations, we show this gap is likely due to quantum confinement and conclude that the magnetic proximity effect is weak in this system. This weakness is disadvantageous for the realization of the quantum anomalous Hall effect, but favorable for spintronic devices which require the preservation of spin-momentum locking at the Fermi level.",

author = "Jiashu Wang and Tianyi Wang and Mykhaylo Ozerov and Zhan Zhang and Joaquin Bermejo-Ortiz and Bac, {Seul Ki} and Hoai Trinh and Maksym Zhukovskyi and Tatyana Orlova and Haile Ambaye and Jong Keum and {de Vaulchier}, {Louis Anne} and Yves Guldner and Dmitry Smirnov and Valeria Lauter and Xinyu Liu and Assaf, {Badih A.}",

note = "Publisher Copyright: {\textcopyright} 2023, Springer Nature Limited.",

year = "2023",

month = dec,

doi = "10.1038/s42005-023-01327-5",

language = "English",

volume = "6",

journal = "Communications Physics",

issn = "2399-3650",

publisher = "Nature Research",

number = "1",

}

TY - JOUR

T1 - Energy gap of topological surface states in proximity to a magnetic insulator

AU - Wang, Jiashu

AU - Wang, Tianyi

AU - Ozerov, Mykhaylo

AU - Zhang, Zhan

AU - Bermejo-Ortiz, Joaquin

AU - Bac, Seul Ki

AU - Trinh, Hoai

AU - Zhukovskyi, Maksym

AU - Orlova, Tatyana

AU - Ambaye, Haile

AU - Keum, Jong

AU - de Vaulchier, Louis Anne

AU - Guldner, Yves

AU - Smirnov, Dmitry

AU - Lauter, Valeria

AU - Liu, Xinyu

AU - Assaf, Badih A.

PY - 2023/12

Y1 - 2023/12

N2 - Topological surface-states can acquire an energy gap when time-reversal symmetry is broken by interfacing with a magnetic insulator. This gap has yet to be measured. Such topological-magnetic insulator heterostructures can host a quantized anomalous Hall effect and can allow the control of the magnetic state of the insulator in a spintronic device. In this work, we observe the energy gap of topological surface-states in proximity to a magnetic insulator using magnetooptical Landau level spectroscopy. We measure Pb1-xSnxSe–EuSe heterostructures grown by molecular beam epitaxy exhibiting a record mobility and low Fermi energy. Through temperature dependent measurements and theoretical calculations, we show this gap is likely due to quantum confinement and conclude that the magnetic proximity effect is weak in this system. This weakness is disadvantageous for the realization of the quantum anomalous Hall effect, but favorable for spintronic devices which require the preservation of spin-momentum locking at the Fermi level.

AB - Topological surface-states can acquire an energy gap when time-reversal symmetry is broken by interfacing with a magnetic insulator. This gap has yet to be measured. Such topological-magnetic insulator heterostructures can host a quantized anomalous Hall effect and can allow the control of the magnetic state of the insulator in a spintronic device. In this work, we observe the energy gap of topological surface-states in proximity to a magnetic insulator using magnetooptical Landau level spectroscopy. We measure Pb1-xSnxSe–EuSe heterostructures grown by molecular beam epitaxy exhibiting a record mobility and low Fermi energy. Through temperature dependent measurements and theoretical calculations, we show this gap is likely due to quantum confinement and conclude that the magnetic proximity effect is weak in this system. This weakness is disadvantageous for the realization of the quantum anomalous Hall effect, but favorable for spintronic devices which require the preservation of spin-momentum locking at the Fermi level.

UR - http://www.scopus.com/inward/record.url?scp=85167414620&partnerID=8YFLogxK

U2 - 10.1038/s42005-023-01327-5

DO - 10.1038/s42005-023-01327-5

M3 - Article

AN - SCOPUS:85167414620

SN - 2399-3650

VL - 6

JO - Communications Physics

JF - Communications Physics

IS - 1

M1 - 200

ER -

Energy gap of topological surface states in proximity to a magnetic insulator

Abstract

Funding

Access to Document

Other files and links

Fingerprint

Cite this