TY - JOUR
T1 - Modulation of Dirac electrons in epitaxial Bi2Se3 ultrathin films on van der Waals ferromagnet Cr2Si2Te6
AU - Kato, Takemi
AU - Sugawara, Katsuaki
AU - Ito, Naohiro
AU - Yamauchi, Kunihiko
AU - Sato, Takumi
AU - Oguchi, Tamio
AU - Takahashi, Takashi
AU - Shiomi, Yuki
AU - Saitoh, Eiji
AU - Sato, Takafumi
N1 - Funding Information:
We thank T. Kawakami, T. Taguchi, and Y. Nakata for their assistance in the ARPES experiments. This work was supported by Grant-in-Aid for Scientific Research on Innovative Areas “Topological Materials Science” (JSPS KAKENHI Grants No. JP15H05853, No. JP18H04215, and No. JP15K21717), “J-Physics” (Grant No. JP18H04311), JST-CREST (Grant No. JPMJCR18T1), JST-PRESTO (Grant No. JPMJPR18L7), Grant-in-Aid for Scientific Research (JSPS KAKENHI Grants No. JP17H01139, No. JP18H01821, No. JP15H02105, No. JP26287071, No. JP19H02424, No. JP19K22124, No. JP19H05600, and No. JP25287079), Research Foundation of the Electrotechnology of Chubu, and World Premier International Research Center, Advanced Institute for Materials Research. N.I. acknowledges support from GP-Spin at Tohoku University.
Publisher Copyright:
© 2020 authors. Published by the American Physical Society.
PY - 2020/8
Y1 - 2020/8
N2 - We investigated the Dirac-cone state and its modulation when an ultrathin film of topological insulator Bi2Se3 was epitaxially grown on a van der Waals ferromagnet Cr2Si2Te6 (CST) by angle-resolved photoemission spectroscopy. We observed a gapless Dirac-cone surface state in six quintuple-layer (6QL) Bi2Se3 on CST, whereas the Dirac cone exhibits a gap of 0.37 eV in its 2QL counterpart. Intriguingly, this gap is much larger than those for Bi2Se3 films on Si(111). We also revealed no discernible change in the gap magnitude across the ferromagnetic transition of CST, suggesting the very small characteristic length and energy scale of the magnetic proximity effect. The present results suggest a crucial role of interfacial coupling for modulating Dirac electrons in topological-insulator hybrids.
AB - We investigated the Dirac-cone state and its modulation when an ultrathin film of topological insulator Bi2Se3 was epitaxially grown on a van der Waals ferromagnet Cr2Si2Te6 (CST) by angle-resolved photoemission spectroscopy. We observed a gapless Dirac-cone surface state in six quintuple-layer (6QL) Bi2Se3 on CST, whereas the Dirac cone exhibits a gap of 0.37 eV in its 2QL counterpart. Intriguingly, this gap is much larger than those for Bi2Se3 films on Si(111). We also revealed no discernible change in the gap magnitude across the ferromagnetic transition of CST, suggesting the very small characteristic length and energy scale of the magnetic proximity effect. The present results suggest a crucial role of interfacial coupling for modulating Dirac electrons in topological-insulator hybrids.
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U2 - 10.1103/PhysRevMaterials.4.084202
DO - 10.1103/PhysRevMaterials.4.084202
M3 - Article
AN - SCOPUS:85092146770
VL - 4
JO - Physical Review Materials
JF - Physical Review Materials
SN - 2475-9953
IS - 8
M1 - 084202
ER -