Presentation Information

[25p-71B-10]Observation of field-free superconducting diode effect in topological superconductor candidate FeTe 0.6Se0.4

〇Utane Nagata1, Aoki Motomi1,2, Daido Akito2,3, Ohshima Ryo1,2, Kasahara Shigeru4, Kasahara Yuichi2,3, Ando Yuichiro1,2, Matsuda Yuji2,3, Yanase Youichi2,3, Shiraishi Masashi1,2 (1.Dept. of Engineering Kyoto Univ., 2.CSRN Kyoto Univ., 3.Dept. of Science Kyoto Univ., 4.Dept. of Science Okayama Univ.)


Superconducting diode effect,Iron-based superconductor,Layered material

The superconducting diode effect (SDE) has been investigated intensively for the application towards non-dissipative circuit. Since the magneto chiral anisotropy is known to play an important role in the SDE, the surface state of topological superconductor (TSC) is gathering attention as a possible system for realizing of the SDE. Here, we observed the SDE in a TSC candidate FeTe0.6Se0.4 (FTS). The SDE is appeared without applying an external magnetic field, i.e., the field-free effect was measured. Additionaly, the sign of the difference of the critical current is independent of the external magnetic field. A detailed investigation of the background physics revealed that the origin of the SDE in FTS was a thermal gradient caused by inhomogeneous device geometry rather than TSC state of FTS. This study experimentally demonstrates the need to consider thermal dissipation, which has received little attention so far, as the origin of time-reversal symmetry breaking in the SDE.