TY - JOUR
T1 - Conversion of a conventional superconductor into a topological superconductor by topological proximity effect
AU - Trang, C. X.
AU - Shimamura, N.
AU - Nakayama, K.
AU - Souma, S.
AU - Sugawara, K.
AU - Watanabe, I.
AU - Yamauchi, K.
AU - Oguchi, T.
AU - Segawa, K.
AU - Takahashi, T.
AU - Ando, Yoichi
AU - Sato, T.
N1 - Funding Information:
We thank T.N., K.H., A.T. and T.R. 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 Grant numbers JP15H05853, JP18H04227, and JP15K21717), JST-CREST (no. JPMJCR18T1), JST-PRESTO (no. JPMJPR18L7), and Grant-in-Aid for Scientific Research (JSPS KAKENHI Grant numbers JP17H01139, JP15H02105, JP26287071, and JP25287079). The work in Cologne was funded by the Deutsche Forschungsgemeinschaft (German Research Foundation) - Project number 277146847 - CRC 1238 (Subproject A04).
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - Realization of topological superconductors (TSCs) hosting Majorana fermions is a central challenge in condensed-matter physics. One approach is to use the superconducting proximity effect (SPE) in heterostructures, where a topological insulator contacted with a superconductor hosts an effective p-wave pairing by the penetration of Cooper pairs across the interface. However, this approach suffers a difficulty in accessing the topological interface buried deep beneath the surface. Here, we propose an alternative approach to realize topological superconductivity without SPE. In a Pb(111) thin film grown on TlBiSe2, we discover that the Dirac-cone state of substrate TlBiSe2 migrates to the top surface of Pb film and obtains an energy gap below the superconducting transition temperature of Pb. This suggests that a Bardeen-Cooper-Schrieffer superconductor is converted into a TSC by the topological proximity effect. Our discovery opens a route to manipulate topological superconducting properties of materials.
AB - Realization of topological superconductors (TSCs) hosting Majorana fermions is a central challenge in condensed-matter physics. One approach is to use the superconducting proximity effect (SPE) in heterostructures, where a topological insulator contacted with a superconductor hosts an effective p-wave pairing by the penetration of Cooper pairs across the interface. However, this approach suffers a difficulty in accessing the topological interface buried deep beneath the surface. Here, we propose an alternative approach to realize topological superconductivity without SPE. In a Pb(111) thin film grown on TlBiSe2, we discover that the Dirac-cone state of substrate TlBiSe2 migrates to the top surface of Pb film and obtains an energy gap below the superconducting transition temperature of Pb. This suggests that a Bardeen-Cooper-Schrieffer superconductor is converted into a TSC by the topological proximity effect. Our discovery opens a route to manipulate topological superconducting properties of materials.
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U2 - 10.1038/s41467-019-13946-0
DO - 10.1038/s41467-019-13946-0
M3 - Article
C2 - 31919356
AN - SCOPUS:85077675666
SN - 2041-1723
VL - 11
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 159
ER -