Superconducting Cavity Probes Sliding Ferroelectricity in Small-Angle Twisted WSe₂

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Ferroelectricity involves spontaneous charge polarization in materials.
• Two-dimensional (2D) materials offer unique properties for electronic devices.
• Sliding ferroelectricity in stacked bilayers (e.g., hBN, TMDCs) creates out-of-plane polarization.

Purpose of the Study:

• To investigate the ferroelectric polarization of small-angle parallel-stacked WSe2.
• To utilize high-frequency AC response measurements for probing ferroelectricity.
• To explore potential applications in memory devices and field-effect transistors.

Main Methods:

• Embedding small-angle parallel-stacked WSe2 into a superconducting coplanar waveguide cavity.
• Measuring the high-frequency AC response, including capacitance and cavity quality factor.
• Analyzing the observed hysteretic responses and relaxation effects.

Main Results:

• Observed hysteretic responses in capacitance and cavity quality factor, confirming ferroelectric switching.
• Detected relaxation effects linked to ferroelectric domain wall motion.
• Demonstrated the feasibility of a cavity-based technique for high-frequency measurements.

Conclusions:

• Ferroelectric switching and domain wall dynamics were confirmed in stacked WSe2.
• The cavity-based technique is effective for probing ferroelectric systems at high frequencies.
• This method holds promise for developing advanced electronic devices and understanding domain wall behavior.