Gate-Controlled Superconducting Switch in GaSe/NbSe₂ van der Waals Heterostructure

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• The increasing demand for low-power devices and advancements in quantum computing necessitate novel materials and device architectures.
• Two-dimensional (2D) superconductors offer unique physical properties for fundamental research and potential applications in integrated circuits and quantum computation.

Purpose of the Study:

• To report a gate-controlled superconducting switch in a GaSe/NbSe2 van der Waals (vdW) heterostructure.
• To demonstrate the modulation of superconducting properties via high-energy electron injection and ferroelectric polarization.

Main Methods:

• Fabrication of a GaSe/NbSe2 vdW heterostructure.
• Induction of a non-equilibrium state in NbSe2 by injecting high-energy electrons under an electric field.
• Utilizing the ferroelectric polarization of GaSe for device control.

Main Results:

• Achieved significant modulation of superconducting properties in NbSe2.
• Demonstrated a steeper subthreshold slope and asymmetric modulation due to GaSe's ferroelectric polarization.
• Successfully realized a superconducting switch that reversibly toggles between superconducting and normal states via electric field control.

Conclusions:

• The study highlights the significant high-energy injection effect in 2D vdW heterostructures.
• Band engineering in heterostructures combining superconductors and ferroelectric semiconductors shows great potential.
• The developed superconducting switch demonstrates promise for applications in superconducting integrated circuits and quantum computation.