摘要(英) |
We fabricated Lead (Pb) clusters/single-layer molybdenum disulphide (MoS2) devices, and mainly studied proximity-induced superconductivity in the system. Electrons in a superconductor are paired into Cooper pairs in superconducting state. In a non-superconducting material decorated with noncontinous superconductors system, Cooper pairs may diffuse into non-superconducting material. If Cooper pairs transport in non-superconducting material without losing their coherence, we can observe entire system turning into superconducting state.
Pb’s dewetting produces self-assembled noncontinous grains on the single-layer MoS2 surface. The spacing between Pb grains decreases with evaporating thicker Pb on the single- layer MoS2 surface. The carrier concentration of single layer MoS2 is tuable by applying gate voltage on devices. By adjusting carrier concentration of MoS2, thickness and spacing of Pb grains, we expect to observe proximity-induced superconductivity in Pb clusters/single layer MoS2 devices.
In our experiment, we measured critical temperature、critical current and critical field of Pb film/ single layer MoS2 devices first. By applying voltage on ploymer electrolyte gate, we tuned the carrier concentration of single layer MoS2 and effectively reduced resistance of the devices. However, most of Pb clusters/ single layer MoS2 devices with ploymer electrolyte gate were burned out during cooling down process. Therefore, we have not observed proximity-induced superconductivity in Pb clusters/single layer MoS2 devices yet. We only observed superconductivity in 50nm Pb film/ single layer MoS2 devices. |
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