Publicly Offered Research
Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
The micro-fabrication technique will be applied to reduce the size of crystal into single domain, and control the shape and geometry for the study of superconductivity and nematicity. In the fabricated devices, transport measurements will be performed to study nematicity, in the whole temperature region from the normal state (e.g. resistivity and magnetoresistance) to the superconducting state (e.g. depairing Jc). Our research will overcome the difficulty of controlling the sample's shape and direction, and open a new route to probe the relation between nematicity and superconductivity.
We sucessfully achieved the depairing Jc in a narrow bridge of FeSe single crystal fabricated by the FIB pick-up technique. Width of the narrow bridge is reduced in sequence from 1.125 μm to 0.388 μm, which is larger and smaller than the value of Pearl length (Λ ~ 0.62 μm), respectively. Jc is directly estimated from the transport current-voltage measurements, which reaches a very large value about one order of magnitude larger than the depinning Jc estimated from the magnetic hysteresis loops (MHLs). Furthermore, the value of Jc is found to be increased more than twice simply by reducing W from 1.125 μm to 0.388 μm, which supports the achievement of depairing Jc. We also measured the Jc under magnetic fields. Jc of the narrow bridge is found to be much stable against magnetic field than that of the bulk sample. The field-insensitive Jc can be understood by the large increase of lower critical field, Hc1, when W is reduced to be comparable to λ
令和3年度が最終年度であるため、記入しない。
All 2021 2020
All Journal Article (8 results) (of which Int'l Joint Research: 8 results, Peer Reviewed: 8 results) Presentation (5 results) (of which Int'l Joint Research: 2 results)
Physical Review B
Volume: 104 Issue: 14
10.1103/physrevb.104.l140504
Volume: 103 Issue: 22 Pages: 224506-224506
10.1103/physrevb.103.224506
Volume: 104 Issue: 1 Pages: 014505-014505
10.1103/physrevb.104.014505
Volume: 103 Issue: 14 Pages: 144501-144501
10.1103/physrevb.103.144501
Superconductor Science and Technology
Volume: 34 Issue: 5 Pages: 055006-055006
10.1088/1361-6668/abef4e
Volume: 101 Issue: 24 Pages: 245102-245102
10.1103/physrevb.101.245102
Science Bulletin
Volume: 65 Issue: 16 Pages: 1349-1355
10.1016/j.scib.2020.04.039
Volume: 102 Issue: 2 Pages: 024517-024517
10.1103/physrevb.102.024517
