Magnetic field enhanced zero-bias conductance in vertical Josephson junctions based on Weyl semimetals

摘要

We report the magnetotransport properties of T_d-MoTe_2 based vertical junctions with NbN superconducting electrodes. Benefiting from the high critical magnetic field of NbN, the superconducting state is maintained up to 8 T. A sharp drop of resistance is observed at T_c ～ 13 K, corresponding to the critical temperature of NbN electrodes. The differential conductance spectra show that the zero-bias conductance is increased by magnetic fields with 41.6% increment at 14 T. Intriguingly, negative magnetoresistance (MR) ～-48% is observed under 8 T at 3 K. The negative MR disappears above superconductivity critical temperature ～13 K. The Weyl semimetal MoTe_2 combined with superconductor is promising for searching topological superconductivity and Majorana zero modes.