Probing the incompatibility between two superconducting condensates in proximitized type II Weyl semimetal MoTe2 devices through the disloyal edge mode

The disloyal edge mode [1] of exfoliated MoTe2 crystals with niobium (Nb) electrodes could be proximitized by either Nb or intrinsic bulk superconducting (SC) condensates. It tended to retain the memory of being proximitized by the bulk condensate, revealing the incompatibility between the two condensates. In a varying magnetic field, MoTe2 nanodevices with Nb electrodes underwent metal-SC and SC-metal transitions. The proximitized edge condensate was manifested by the modulations of critical current in differential resistance versus applied magnetic field spectra, where the areas associated with the frequencies of modulations corresponded to physical areas of samples. During the SC-metal transition, the field intervals between critical current modulations were regular, while those for the opposite transition were irregular. Cuts of such spectra at zero bias current exhibited anti-hysteretic changes of resistance during phase transitions. The differential resistance increased prematurely during the SC-metal transition, and vice versa for the opposite transition. Such observations showed that the edge mode was dominated by the bulk condensate during SC-metal transition, while it attached to the Nb condensate but interrupted by the bulk condensate during the opposite transition.