Description:

The recent discovery of intrinsic supercurrent diode effect [1], and its prompt observation in a richvariety of systems, has shown that nonreciprocal supercurrents naturally emerge when
both space-and time-inversion symmetries are broken. I will report on ac-manifestations of the diode effect in the non-linear inductance in planar Josephson junctions, based on a ballistic AI/InAs-heterostructure that is exposed to an in-plane magnetic field Bip [2]. At low Bip a non-reciprocal term is found in the inductance that is linear in Bip. At higher Bip a sign reversal of the magnetochiral term is observed that can be traced back to a 0-π -like transition in the current-phase relation.

In a small perpendicular magnetic field, also the unpatterned heterostructure features a large inductance which results from the oscillations of pinned vortices around pinning centers. The vortex inductance is inversely proportional to the pinning potential. If a parallel field is applied in addition, the vortex inductance unexpectedly decreases in a anisotropic fashion. This observation can be understood as an anisotropic squeezing of the vortex cores, which is consequence of Lifschitz invarients in the free energy of our non-centrosymmetic hetero- structure [3].

[1] F. Ando et al., Nature 584, 373 (2020).
[2] C. Baumgartner, et al., Nature Nanotech. 17, 39 (2022).
[3] L. Fuchs, et al., Phys. Rev. X 12, 041020 (2022).