The oxide interface between LaAlO₃ and KTaO₃(111) can harbor a superconducting state. We report that by applying a gate voltage (V_G) across KTaO₃, the interface can be continuously tuned from superconducting into insulating states, yielding a dome-shaped T_c-V_G dependence, where T_c is the transition temperature. The electric gating has only a minor effect on carrier density but a strong one on mobility. We interpret the tuning of mobility in terms of change in the spatial profile of the carriers in the interface and hence, effective disorder. As the temperature is decreased, the resistance saturates at the lowest temperature on both superconducting and insulating sides, suggesting the emergence of a quantum metallic state associated with a failed superconductor and/or fragile insulator.

LaAlO ₃和KTaO ₃（111）之间的氧化物界面可以具有超导状态。我们报告说，通过在KTaO _3上施加栅极电压（V _G），可以将界面从超导连续调谐到绝缘态，从而产生圆顶形的T _c - V _G依赖性，其中T _c是转变温度。电气门控对载流子密度的影响很小，而对迁移率的影响却很大。我们根据接口中载体空间分布的变化来解释迁移率的调整，从而解释有效的无序性。随着温度降低，超导和绝缘两面的电阻均在最低温度下饱和，这表明出现了与失效的超导体和/或易碎的绝缘体有关的量子金属态。