Large-Gap Magnetic Topological Heterostructure Formed by Subsurface Incorporation of a Ferromagnetic Layer

Toru Hirahara, Sergey V. Eremeev, Tetsuroh Shirasawa, Yuma Okuyama, Takayuki Kubo, Ryosuke Nakanishi, Ryota Akiyama, Akari Takayama, Tetsuya Hajiri, Shin Ichiro Ideta, Masaharu Matsunami, Kazuki Sumida, Koji Miyamoto, Yasumasa Takagi, Kiyohisa Tanaka, Taichi Okuda, Toshihiko Yokoyama, Shin Ichi Kimura, Shuji Hasegawa, Evgueni V. Chulkov

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

Inducing magnetism into topological insulators is intriguing for utilizing exotic phenomena such as the quantum anomalous Hall effect (QAHE) for technological applications. While most studies have focused on doping magnetic impurities to open a gap at the surface-state Dirac point, many undesirable effects have been reported to appear in some cases that makes it difficult to determine whether the gap opening is due to the time-reversal symmetry breaking or not. Furthermore, the realization of the QAHE has been limited to low temperatures. Here we have succeeded in generating a massive Dirac cone in a MnBi2Se4/Bi2Se3 heterostructure, which was fabricated by self-assembling a MnBi2Se4 layer on top of the Bi2Se3 surface as a result of the codeposition of Mn and Se. Our experimental results, supported by relativistic ab initio calculations, demonstrate that the fabricated MnBi2Se4/Bi2Se3 heterostructure shows ferromagnetism up to room temperature and a clear Dirac cone gap opening of ∼100 meV without any other significant changes in the rest of the band structure. It can be considered as a result of the direct interaction of the surface Dirac cone and the magnetic layer rather than a magnetic proximity effect. This spontaneously formed self-assembled heterostructure with a massive Dirac spectrum, characterized by a nontrivial Chern number C = -1, has a potential to realize the QAHE at significantly higher temperatures than reported up to now and can serve as a platform for developing future "topotronics" devices.

Original languageEnglish
Pages (from-to)3493-3500
Number of pages8
JournalNano Letters
Volume17
Issue number6
DOIs
Publication statusPublished - 2017 Jun 14
Externally publishedYes

Fingerprint

Quantum Hall effect
Hall effect
Heterojunctions
Cones
cones
Ferromagnetism
Magnetism
Surface states
assembling
Band structure
Temperature
ferromagnetism
broken symmetry
platforms
Doping (additives)
insulators
Impurities
impurities
room temperature
interactions

Keywords

  • magnetism
  • massive Dirac cone
  • quantum anomalous Hall effect
  • Topological insulators

ASJC Scopus subject areas

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering

Cite this

Hirahara, T., Eremeev, S. V., Shirasawa, T., Okuyama, Y., Kubo, T., Nakanishi, R., ... Chulkov, E. V. (2017). Large-Gap Magnetic Topological Heterostructure Formed by Subsurface Incorporation of a Ferromagnetic Layer. Nano Letters, 17(6), 3493-3500. https://doi.org/10.1021/acs.nanolett.7b00560

Large-Gap Magnetic Topological Heterostructure Formed by Subsurface Incorporation of a Ferromagnetic Layer. / Hirahara, Toru; Eremeev, Sergey V.; Shirasawa, Tetsuroh; Okuyama, Yuma; Kubo, Takayuki; Nakanishi, Ryosuke; Akiyama, Ryota; Takayama, Akari; Hajiri, Tetsuya; Ideta, Shin Ichiro; Matsunami, Masaharu; Sumida, Kazuki; Miyamoto, Koji; Takagi, Yasumasa; Tanaka, Kiyohisa; Okuda, Taichi; Yokoyama, Toshihiko; Kimura, Shin Ichi; Hasegawa, Shuji; Chulkov, Evgueni V.

In: Nano Letters, Vol. 17, No. 6, 14.06.2017, p. 3493-3500.

Research output: Contribution to journalArticle

Hirahara, T, Eremeev, SV, Shirasawa, T, Okuyama, Y, Kubo, T, Nakanishi, R, Akiyama, R, Takayama, A, Hajiri, T, Ideta, SI, Matsunami, M, Sumida, K, Miyamoto, K, Takagi, Y, Tanaka, K, Okuda, T, Yokoyama, T, Kimura, SI, Hasegawa, S & Chulkov, EV 2017, 'Large-Gap Magnetic Topological Heterostructure Formed by Subsurface Incorporation of a Ferromagnetic Layer', Nano Letters, vol. 17, no. 6, pp. 3493-3500. https://doi.org/10.1021/acs.nanolett.7b00560
Hirahara T, Eremeev SV, Shirasawa T, Okuyama Y, Kubo T, Nakanishi R et al. Large-Gap Magnetic Topological Heterostructure Formed by Subsurface Incorporation of a Ferromagnetic Layer. Nano Letters. 2017 Jun 14;17(6):3493-3500. https://doi.org/10.1021/acs.nanolett.7b00560
Hirahara, Toru ; Eremeev, Sergey V. ; Shirasawa, Tetsuroh ; Okuyama, Yuma ; Kubo, Takayuki ; Nakanishi, Ryosuke ; Akiyama, Ryota ; Takayama, Akari ; Hajiri, Tetsuya ; Ideta, Shin Ichiro ; Matsunami, Masaharu ; Sumida, Kazuki ; Miyamoto, Koji ; Takagi, Yasumasa ; Tanaka, Kiyohisa ; Okuda, Taichi ; Yokoyama, Toshihiko ; Kimura, Shin Ichi ; Hasegawa, Shuji ; Chulkov, Evgueni V. / Large-Gap Magnetic Topological Heterostructure Formed by Subsurface Incorporation of a Ferromagnetic Layer. In: Nano Letters. 2017 ; Vol. 17, No. 6. pp. 3493-3500.
@article{e63ac05311084742a66a1f45797e968c,
title = "Large-Gap Magnetic Topological Heterostructure Formed by Subsurface Incorporation of a Ferromagnetic Layer",
abstract = "Inducing magnetism into topological insulators is intriguing for utilizing exotic phenomena such as the quantum anomalous Hall effect (QAHE) for technological applications. While most studies have focused on doping magnetic impurities to open a gap at the surface-state Dirac point, many undesirable effects have been reported to appear in some cases that makes it difficult to determine whether the gap opening is due to the time-reversal symmetry breaking or not. Furthermore, the realization of the QAHE has been limited to low temperatures. Here we have succeeded in generating a massive Dirac cone in a MnBi2Se4/Bi2Se3 heterostructure, which was fabricated by self-assembling a MnBi2Se4 layer on top of the Bi2Se3 surface as a result of the codeposition of Mn and Se. Our experimental results, supported by relativistic ab initio calculations, demonstrate that the fabricated MnBi2Se4/Bi2Se3 heterostructure shows ferromagnetism up to room temperature and a clear Dirac cone gap opening of ∼100 meV without any other significant changes in the rest of the band structure. It can be considered as a result of the direct interaction of the surface Dirac cone and the magnetic layer rather than a magnetic proximity effect. This spontaneously formed self-assembled heterostructure with a massive Dirac spectrum, characterized by a nontrivial Chern number C = -1, has a potential to realize the QAHE at significantly higher temperatures than reported up to now and can serve as a platform for developing future {"}topotronics{"} devices.",
keywords = "magnetism, massive Dirac cone, quantum anomalous Hall effect, Topological insulators",
author = "Toru Hirahara and Eremeev, {Sergey V.} and Tetsuroh Shirasawa and Yuma Okuyama and Takayuki Kubo and Ryosuke Nakanishi and Ryota Akiyama and Akari Takayama and Tetsuya Hajiri and Ideta, {Shin Ichiro} and Masaharu Matsunami and Kazuki Sumida and Koji Miyamoto and Yasumasa Takagi and Kiyohisa Tanaka and Taichi Okuda and Toshihiko Yokoyama and Kimura, {Shin Ichi} and Shuji Hasegawa and Chulkov, {Evgueni V.}",
year = "2017",
month = "6",
day = "14",
doi = "10.1021/acs.nanolett.7b00560",
language = "English",
volume = "17",
pages = "3493--3500",
journal = "Nano Letters",
issn = "1530-6984",
publisher = "American Chemical Society",
number = "6",

}

TY - JOUR

T1 - Large-Gap Magnetic Topological Heterostructure Formed by Subsurface Incorporation of a Ferromagnetic Layer

AU - Hirahara, Toru

AU - Eremeev, Sergey V.

AU - Shirasawa, Tetsuroh

AU - Okuyama, Yuma

AU - Kubo, Takayuki

AU - Nakanishi, Ryosuke

AU - Akiyama, Ryota

AU - Takayama, Akari

AU - Hajiri, Tetsuya

AU - Ideta, Shin Ichiro

AU - Matsunami, Masaharu

AU - Sumida, Kazuki

AU - Miyamoto, Koji

AU - Takagi, Yasumasa

AU - Tanaka, Kiyohisa

AU - Okuda, Taichi

AU - Yokoyama, Toshihiko

AU - Kimura, Shin Ichi

AU - Hasegawa, Shuji

AU - Chulkov, Evgueni V.

PY - 2017/6/14

Y1 - 2017/6/14

N2 - Inducing magnetism into topological insulators is intriguing for utilizing exotic phenomena such as the quantum anomalous Hall effect (QAHE) for technological applications. While most studies have focused on doping magnetic impurities to open a gap at the surface-state Dirac point, many undesirable effects have been reported to appear in some cases that makes it difficult to determine whether the gap opening is due to the time-reversal symmetry breaking or not. Furthermore, the realization of the QAHE has been limited to low temperatures. Here we have succeeded in generating a massive Dirac cone in a MnBi2Se4/Bi2Se3 heterostructure, which was fabricated by self-assembling a MnBi2Se4 layer on top of the Bi2Se3 surface as a result of the codeposition of Mn and Se. Our experimental results, supported by relativistic ab initio calculations, demonstrate that the fabricated MnBi2Se4/Bi2Se3 heterostructure shows ferromagnetism up to room temperature and a clear Dirac cone gap opening of ∼100 meV without any other significant changes in the rest of the band structure. It can be considered as a result of the direct interaction of the surface Dirac cone and the magnetic layer rather than a magnetic proximity effect. This spontaneously formed self-assembled heterostructure with a massive Dirac spectrum, characterized by a nontrivial Chern number C = -1, has a potential to realize the QAHE at significantly higher temperatures than reported up to now and can serve as a platform for developing future "topotronics" devices.

AB - Inducing magnetism into topological insulators is intriguing for utilizing exotic phenomena such as the quantum anomalous Hall effect (QAHE) for technological applications. While most studies have focused on doping magnetic impurities to open a gap at the surface-state Dirac point, many undesirable effects have been reported to appear in some cases that makes it difficult to determine whether the gap opening is due to the time-reversal symmetry breaking or not. Furthermore, the realization of the QAHE has been limited to low temperatures. Here we have succeeded in generating a massive Dirac cone in a MnBi2Se4/Bi2Se3 heterostructure, which was fabricated by self-assembling a MnBi2Se4 layer on top of the Bi2Se3 surface as a result of the codeposition of Mn and Se. Our experimental results, supported by relativistic ab initio calculations, demonstrate that the fabricated MnBi2Se4/Bi2Se3 heterostructure shows ferromagnetism up to room temperature and a clear Dirac cone gap opening of ∼100 meV without any other significant changes in the rest of the band structure. It can be considered as a result of the direct interaction of the surface Dirac cone and the magnetic layer rather than a magnetic proximity effect. This spontaneously formed self-assembled heterostructure with a massive Dirac spectrum, characterized by a nontrivial Chern number C = -1, has a potential to realize the QAHE at significantly higher temperatures than reported up to now and can serve as a platform for developing future "topotronics" devices.

KW - magnetism

KW - massive Dirac cone

KW - quantum anomalous Hall effect

KW - Topological insulators

UR - http://www.scopus.com/inward/record.url?scp=85020770127&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85020770127&partnerID=8YFLogxK

U2 - 10.1021/acs.nanolett.7b00560

DO - 10.1021/acs.nanolett.7b00560

M3 - Article

VL - 17

SP - 3493

EP - 3500

JO - Nano Letters

JF - Nano Letters

SN - 1530-6984

IS - 6

ER -