Acoustically Induced Giant Synthetic Hall Voltages in Graphene

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Graphene's unique electronic properties are sensitive to its flatness, with deviations inducing artificial gauge fields and pseudomagnetic fields.
• These gauge fields influence the motion of Dirac fermions, which are key charge carriers in graphene.

Purpose of the Study:

• To demonstrate the tunability of strong gauge fields in large planar graphene systems.
• To investigate the generation of synthetic Hall voltages using surface acoustic waves.
• To explore the interplay between synthetic and conventional Hall effects.

Main Methods:

• Utilizing nonlocal experiments with a large planar graphene sheet conformally mapped onto a piezoelectric substrate.
• Applying surface acoustic waves to deform the graphene sheet and induce artificial gauge fields.
• Measuring longitudinal and synthetic Hall voltages in the absence of external magnetic fields.

Main Results:

• Surface acoustic waves successfully induced tunable, strong gauge fields in graphene.
• A giant synthetic Hall voltage was observed without external magnetic fields.
• The superposition of synthetic and conventional Hall voltages allowed for the annihilation of the transverse potential.

Conclusions:

• Surface acoustic waves provide a facile method for exploiting gauge fields in large graphene systems.
• This technique enables the dynamic control of Dirac fermion behavior through tunable artificial gauge fields.
• The findings open avenues for novel electronic devices based on engineered gauge fields in graphene.