A Two-Dimensional\nSuperconducting Electron Gas at\nLaFeO<sub>3</sub>/SrTiO<sub>3</sub> Interfaces

Transition metal oxide interfaces have garnered great\nattention\ndue to their fascinating properties that are absent in their bulk\ncounterparts. The high mobility and coexistence of superconductivity\nand magnetism at these interfaces remain compelling research topics.\nHere, we first report superconductivity in the 2DEG formed at the\nLaFeO<sub>3</sub>/SrTiO<sub>3</sub> interfaces, characterized by a\nsuperconducting transition temperature (<i>T</i><sub>c</sub>) of 333 mK and a superconducting layer thickness of 13.7 nm. The\nobservation of a Berezinskii-Kosterlitz-Thouless transition at low\ntemperatures indicates the two-dimensional nature of the superconductivity.\nSuch two-dimensional superconductivity can be tuned by applying a\ngate voltage (<i>V</i><sub>g</sub>) across the SrTiO<sub>3</sub> substrate, showing a dome-shaped <i>T</i><sub>c</sub>–<i>V</i><sub>g</sub> dependence. Moreover, we observe\na hysteretic behavior in the magnetoresistance in the superconducting\nregime, and the underlying mechanism requires further investigation.\nOur results unveil the superconducting characteristics of 2DEG at\nLaFeO<sub>3</sub>/SrTiO<sub>3</sub> interfaces and offer a new compelling\nplatform to investigate emergent quantum phenomena at oxide interfaces.