Josephson junctions of Weyl semimetal ${\text{WTe}}_2$ induced by spontaneous nucleation of $\text{PdTe}$ superconductor

We report on the fabrication of Josephson junction devices with weak links utilizing the Weyl and higher-order topological semimetal ${\text{WTe}}_2$. We show that ${\text{WTe}}_2\text{/Pd}$ contact annealed at a low temperature of 80{\deg}C did not exhibit superconducting properties because neither ${\text{WTe}}_2$ nor Pd are superconductors in the ground state. Upon 180{\deg}C annealing, spontaneous formation of superconducting $\text{PdTe}$ due to Pd diffusion enabled us to obtain the interface between ${\text{WTe}}_2$ and superconductor suitable for the Josephson junction. This result is a facile technique to make a Josephson junction and induce Cooper pairs into topological telluride semimetals.