Extrinsic and Intrinsic Nonlinear Planar Hall Effect in T_d-MoTe₂.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Mechanics

Background:

• Ternary transition metal dichalcogenides (TMDs) exhibit unique electronic properties.
• Broken inversion symmetry in semimetals can lead to novel transport phenomena.
• Nonlinear transport effects are sensitive probes of band structure geometry.

Purpose of the Study:

• To investigate the nonlinear planar Hall effect in Td-molybdenum ditelluride (MoTe2).
• To explore the relationship between band structure geometry and nonlinear transport.
• To identify potential applications in electronic devices and sensing.

Main Methods:

• Experimental observation of the nonlinear Hall voltage in Td-MoTe2 across a temperature range of 2-150 K.
• Analysis of the voltage scaling with applied electric and magnetic fields.
• First-principles calculations to understand the underlying physical mechanisms.
• Scaling analysis of experimental data.

Main Results:

• A distinct nonlinear planar Hall effect was observed in Td-MoTe2.
• The Hall voltage exhibited quadratic dependence on the electric field and linear dependence on the magnetic field.
• Specific angular dependencies (cosine and sine relationships) were identified based on electric field alignment.
• Two contributions to the nonlinear Hall effect were distinguished: intrinsic (Berry connection polarizability) and extrinsic (nonlinear Drude-like).

Conclusions:

• The study expands the understanding of nonlinear Hall transport in low-symmetry materials.
• The findings highlight the role of quantum geometry in nonlinear transport phenomena.
• Td-MoTe2 shows promise for applications in precision magnetic field sensing and directional electronic devices.