Effect of electrolyte gating on the superconducting properties of thin 2H-NbSe2 platelets

Polymer electrolyte gating is a technique that may combine electro-chemical doping with electrostatic gating. Here we report the tuning of superconductivity in micrometer-sized thin 2H-NbSe2 platelets using a mixture of LiClO4 and polyethylene oxide. We show that both negative and positive gate voltages can influence the superconducting transition temperature. The former has a weak effect, while the latter can suppress the transition within our measurement range (down to 2 K). Furthermore, such suppression can be partially restored by removing the gate voltage. The charge density wave transition in the material can also be influenced by the gate voltage, as demonstrated by investigating the temperature dependence of the Hall coefficient. Our results suggest that the electrolyte gating technique can be an efficient way to continuously tune superconducting behavior in layered materials.