TY - JOUR
T1 - Superconducting gap and pseudogap in the surface states of the iron-based superconductor PrFeAsO1-y studied by angle-resolved photoemission spectroscopy
AU - Hagiwara, K.
AU - Ishikado, M.
AU - Horio, M.
AU - Koshiishi, K.
AU - Nakata, S.
AU - Ideta, S.
AU - Tanaka, K.
AU - Horiba, K.
AU - Ono, K.
AU - Kumigashira, H.
AU - Yoshida, T.
AU - Ishida, S.
AU - Eisaki, H.
AU - Shamoto, S.
AU - Fujimori, A.
N1 - Funding Information:
Part of this work was conducted at Advanced Characterization Nanotechnology Platform of the University of Tokyo, supported by “Nanotechnology Platform” of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan. Sample characterization was performed by using a SQUID magnetometer at the CROSS user laboratory. ARPES experiments were performed at UVSOR (Proposal No. 29-546). Preliminary experiment was done at KEK-PF under the approval of the Program Advisory Committee (Proposals No. 2015S2-003 and No. 2016G096). This work was supported by KAKENHI Grants No. 15H02109 and No. 19K03741 from JSPS and by “Program for Promoting Researches on the Supercomputer Fugaku” (Basic Science for Emergence and Functionality in Quantum Matter, JPMXP1020200104) from MEXT.
Publisher Copyright:
© 2021 authors.
PY - 2021/12
Y1 - 2021/12
N2 - In order to study the possible superconductivity at the polar surfaces of 1111-type iron-based superconductors, which is doped with a large amount of holes in spite of the electron doping in bulk materials, we have performed angle-resolved photoemission spectroscopy (ARPES) studies on superconducting PrFeAsO1-y crystals. We have indeed observed the opening of a superconducting gap on surface-derived hole pockets as well as on a bulk-derived hole pocket. The superconducting gap is found to open on the surface-derived hole pockets below the bulk Tc, which suggests that the surface superconductivity is possibly induced by proximity effect from the bulk. We have also observed the opening of a large pseudogap on the surface-derived hole pockets, which is similar to the pseudogap in 122-type bulk superconductors doped with a smaller amount of holes. This suggests that the opening of a large pseudogap is a characteristic property of hole-doped iron-based superconductors.
AB - In order to study the possible superconductivity at the polar surfaces of 1111-type iron-based superconductors, which is doped with a large amount of holes in spite of the electron doping in bulk materials, we have performed angle-resolved photoemission spectroscopy (ARPES) studies on superconducting PrFeAsO1-y crystals. We have indeed observed the opening of a superconducting gap on surface-derived hole pockets as well as on a bulk-derived hole pocket. The superconducting gap is found to open on the surface-derived hole pockets below the bulk Tc, which suggests that the surface superconductivity is possibly induced by proximity effect from the bulk. We have also observed the opening of a large pseudogap on the surface-derived hole pockets, which is similar to the pseudogap in 122-type bulk superconductors doped with a smaller amount of holes. This suggests that the opening of a large pseudogap is a characteristic property of hole-doped iron-based superconductors.
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U2 - 10.1103/PhysRevResearch.3.043151
DO - 10.1103/PhysRevResearch.3.043151
M3 - Article
AN - SCOPUS:85122512896
VL - 3
JO - Physical Review Research
JF - Physical Review Research
SN - 2643-1564
IS - 4
M1 - 043151
ER -