Gate-Controlled Superconducting Switch in GaSe/NbSe van der Waals Heterostructure.

The demand for low-power devices is on the rise as semiconductor engineering approaches the quantum limit, and quantum computing continues to advance. Two-dimensional (2D) superconductors, thanks to their rich physical properties, hold significant promise for both fundamental physics and potential applications in superconducting integrated circuits and quantum computation. Here, we report a gate-controlled superconducting switch in GaSe/NbSe van der Waals (vdW) heterostructure. By injecting high-energy electrons into NbSe under an electric field, a non-equilibrium state is induced, resulting in significant modulation of the superconducting properties. Owing to the intrinsic polarization of ferroelectric GaSe, a much steeper subthreshold slope and asymmetric modulation are achieved, which is beneficial for the device performance. Based on these results, a superconducting switch is realized that can reversibly and controllably switch between the superconducting and normal states under an electric field. Our findings highlight the significant high-energy injection effect from band engineering in 2D vdW heterostructures combining superconductors and ferroelectric semiconductors and demonstrate the potential for applications in superconducting integrated circuits.