Nonlinear Hall Effect in a Semiconductor Heterostructure with Rashba and Dresselhaus Effects

We report a nonlinear Hall effect in a high-mobility InAs quantum-well two-dimensional electron gas (2DEG) with coexisting Rashba and Dresselhaus spin-orbit interactions. Under zero magnetic field, a second-harmonic transverse electric field emerges that scales quadratically with current density and is significantly larger than the second-harmonic longitudinal response. Angle-dependent measurements reveal a pronounced 2-fold anisotropy that follows the combined spin-orbit field. This 2-fold symmetry reflects the anisotropic spin-orbit field generated by coexisting Rashba and Dresselhaus interactions rather than crystal symmetry. The normalized signal reaches ∼10-9 V-1 m and persists up to room temperature. Conductivity scaling shows a quadratic dependence consistent with skew-scattering-dominated transport. These results establish conventional semiconductor 2DEGs as a promising platform for spin-orbit-driven nonlinear transport and rectification functionalities.