TY - JOUR
T1 - Unconventional superconductivity in the single-atom-layer alloy Si(111)-√3×√3-(Tl, Pb)
AU - Nakamura, T.
AU - Kim, H.
AU - Ichinokura, S.
AU - Takayama, A.
AU - Zotov, A. V.
AU - Saranin, A. A.
AU - Hasegawa, Y.
AU - Hasegawa, S.
N1 - Funding Information:
We acknowledge fruitful discussion with R. Akiyama and R. Hobara, and also financial support from the Japan Society of Promotion of Science (KAKENHI Grants No. 15H02105, No. 16H02108, No. 25246025, and No. 22246006), Japan-Russia Bilateral Program, MEXT (Grant-in-Aid for Scientific Research on Innovative Areas “Molecular Architectonics,” Grant No. 25110010), and the Russian Foundation for Basic Research (Grant No. 16-52-50049).
Publisher Copyright:
© 2018 American Physical Society.
PY - 2018/10/16
Y1 - 2018/10/16
N2 - We present results of low-temperature scanning tunneling microscopy/spectroscopy measurements on the one-atom-layer superconductor, Si(111)-√3×√3-(Tl,Pb) which has a spin-split band structure due to the Rashba-Bychkov effect. It was revealed that it has a multiple superconducting gap Δ with significant anisotropy and sizable magnitude of 2Δ/kBTC∼8.6(kB is the Boltzmann constant and TC is the critical superconducting temperature). Under the magnetic field, a dip structure was observed even at the core of the vortex. The dip structure was like a "pseudogap" because it remained up to 2 T, well above the upper critical magnetic field determined in the transport measurements (∼0.7 T). This unconventional behavior suggests the possibility of spin-triplet Cooper pairs related to parity-broken superconductors.
AB - We present results of low-temperature scanning tunneling microscopy/spectroscopy measurements on the one-atom-layer superconductor, Si(111)-√3×√3-(Tl,Pb) which has a spin-split band structure due to the Rashba-Bychkov effect. It was revealed that it has a multiple superconducting gap Δ with significant anisotropy and sizable magnitude of 2Δ/kBTC∼8.6(kB is the Boltzmann constant and TC is the critical superconducting temperature). Under the magnetic field, a dip structure was observed even at the core of the vortex. The dip structure was like a "pseudogap" because it remained up to 2 T, well above the upper critical magnetic field determined in the transport measurements (∼0.7 T). This unconventional behavior suggests the possibility of spin-triplet Cooper pairs related to parity-broken superconductors.
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U2 - 10.1103/PhysRevB.98.134505
DO - 10.1103/PhysRevB.98.134505
M3 - Article
AN - SCOPUS:85055124392
SN - 2469-9950
VL - 98
JO - Physical Review B-Condensed Matter
JF - Physical Review B-Condensed Matter
IS - 13
M1 - 134505
ER -