Gate-Tunable Multiband Transport in ZrTe₅ Thin Devices

Area of Science:

• Condensed Matter Physics
• Materials Science
• Topological Materials

Background:

• Zirconium Telluride (ZrTe5) shows promise for topological electronic states.
• Unusual transport behaviors like resistivity peaks and anomalous Hall effect in ZrTe5 lack clear mechanistic understanding.

Purpose of the Study:

• To fabricate high-quality ZrTe5 thin devices for systematic transport measurements.
• To elucidate the mechanisms behind the characteristic resistance peak and anomalous Hall effect in ZrTe5.
• To explore the potential of ZrTe5 in the two-dimensional limit for novel topological states.

Main Methods:

• Utilized a clean dry-transfer fabrication method in an inert environment.
• Developed dual-gate tunable ZrTe5 thin devices exhibiting ambipolar field effects.
• Conducted systematic studies of resistance and Hall effect across various doping densities and temperatures.
• Performed theoretical calculations for model validation.

Main Results:

• Achieved high-quality ZrTe5 thin devices with tunable ambipolar field effects.
• Observed and analyzed the resistance peak and Hall effect, attributing them to electron-hole asymmetry and multiple-carrier transport.
• Validated experimental findings with a simplified semiclassical two-band model.

Conclusions:

• Resolved longstanding puzzles regarding the transport mechanisms in ZrTe5.
• The study provides a clear model explaining the observed phenomena in ZrTe5.
• Paved the way for future research and potential realization of novel topological states in 2D ZrTe5 systems.