We report a superinsulatinglike behavior, in a device having granular Pb film on back-gated few-layer ${\mathrm{MoS}}_2$, below an onset temperature same as the critical temperature $T_{\mathrm{C}}\approx 7\mathrm{K}$ of bulk Pb. Below $T_{\mathrm{C}}$, the current-voltage characteristics exhibit a threshold voltage marking a crossover between the low-bias insulating and the high-bias normal-resistance states, consistent with the known superinsulating state behavior. A temperature-dependent critical magnetic field is also found above which the insulating behavior is suppressed. The threshold voltage is found to vary with the gate voltage but the critical field remains unchanged. With reducing temperature, the sample conductance saturates to a finite value, which depends on magnetic field and gate voltage. This saturation behavior is found to be inconsistent with the charge-Berezinskii-Kosterlitz-Thouless and the thermal activation models but it can be fitted well to a combination of thermal activation and quantum fluctuations.

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• Superconductor-insulator transition
• 2-dimensional systems
• Transition metal dichalcogenides
• Resistivity measurements