Hall Effect Modulation via Ionic Gating in Degenerate Oxide Semiconductors

Area of Science:

• Solid State Physics
• Materials Science
• Semiconductor Physics

Background:

• Hall measurements are crucial for semiconductor characterization but face limitations with highly conductive materials.
• Degenerate semiconductors and traditional gating methods present challenges in modulating carrier density.
• Electric field screening effects obscure carrier behavior in high electron density materials.

Purpose of the Study:

• To investigate ionic gating effects in degenerate semiconductors.
• To demonstrate an unconventional Hall response in indium-tin oxide using water-in-salt electrolytes.
• To enable the observation of a metallic-to-semiconducting transition via ionic gating.

Main Methods:

• Utilized water-in-salt electrolyte-mediated ionic gating.
• Performed in situ Hall measurements to analyze carrier behavior.
• Quantitatively analyzed charge modulation patterns and energy band structure modifications.

Main Results:

• Observed an unconventional Hall response in indium-tin oxide.
• Demonstrated a metallic-to-semiconducting shift induced by ionic gating.
• Quantified charge modulation leading to significant energy band structure changes.

Conclusions:

• Ionic gating provides a novel framework for studying degenerate semiconductors.
• This method overcomes limitations of traditional Hall measurements and gating techniques.
• Facilitates advanced characterization of emerging semiconductor materials for electronic devices.