Search arXivSearch

arXiv · 2506.22739

Anisotropic nonlinear transport in two-dimensional ferroelectrics

Abstract

The longitudinal nonlinear response plays a crucial role in the nonreciprocal charge transport and may provide a simple electrical means to probe the spin-orbit coupling, magnetic order and polarization states, etc. Here, we report on a study on the polarization and magnetic field control of longitudinal nonlinear transport in two-dimensional (2D) ferroelectrics with in-plane polarization. Based on the Boltzmann transport theory, we first study that using a general Hamiltonian model and show that the nonlinear conductivity can be significantly tuned by the polarization and magnetic field. In addition, the nonlinear conductivity reveals a strong spatial anisotropy. We further derive the analytical formulas for the anisotropic nonlinear conductivity in exact accordance with numerical results. Then, we exemplify those phenomena in the 2D ferroelectric SnTe monolayer in the presence of an external magnetic field based on the density functional theory calculations. It is also revealed that the polarity of nonlinear conductivity is locked to the direction of the polarization, thus pointing to the possibility of the nonlinear detection of polarization states. Our work uncovers intriguing features of the longitudinal nonlinear transport in 2D ferroelectrics and provides guidelines for designing the polarization control of rectifying devices.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Qin Zhang, Xu Chen, Mingbo Dou, M. Ye. Zhuravlev, A. V. Nikolaev, Xianjie Wang, L. L. Tao. 2025-06-28. Anisotropic nonlinear transport in two-dimensional ferroelectrics. https://arxiv.org/abs/2506.22739

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Gapped out-of-phase plasmon modes in alternating-twist multilayer graphene

We theoretically investigate the plasmon modes of alternating-twist multilayer graphene. In multilayer systems, interlayer coupling gives rise to distinctive plasmon modes, but calculations in moiré systems remain challenging due to their complex tunneling structures. Using the Kac-Murdock-Szegő Toeplitz formalism, we derive that the in-phase mode exhibits the conventional $\sqrt{q}$ behavior, while the out-of-phase modes acquire plasmon gaps determined by specific interband transitions between Dirac cones with different velocities in the long-wavelength limit. We demonstrate that these out-of-phase modes remain undamped in the weak Coulomb-interaction limit when the twist angle exceeds a critical value ($θ\gtrsim 2.75^\circ$ for the alternating-twist trilayer case), regardless of the carrier density as long as the low-energy effective Dirac Hamiltonian remains valid. Furthermore, we consider the effect of a perpendicular electric field, and demonstrate how plasmon modes can be tuned by a gate voltage.

cond-mat.mes-hall

Optical properties of hydrogenated graphene superlattices

We investigate with first principles theoretical methods optical response accounting for excitonic effects of quasi-one dimensional monolithic arrays of graphene nanostripes -- two-dimensional graphene superlattices, where quasi-metallic and dielectric regions alternate by selective hydrogenation of graphene. It is shown that chemical engineering of the graphene surface can lead to strong and well-isolated absorption peaks in the far-infrared and possibly even terahertz frequencies. The band gap scaling suggests no excitonic insulators.

cond-mat.mes-hall

Long-lived Laughlin pairs in a depleted quantum Hall edge channel

On-demand sources and mesoscopic beam splitters allow individual ballistic electrons to collide in depleted quantum Hall edge channels, where their unscreened Coulomb interaction acts as a strong, controllable nonlinearity. Theory suggests a more striking possibility: in a strong magnetic field, the same repulsion can drive quantized relative circulation, allowing two electrons to propagate together as a positive-energy Laughlin pair. The relevance of such pairs to experiment depends on lifetimes in realistic guiding potentials and on whether the proposed collision pathway to pair formation survives full two-dimensional dynamics. We develop a microscopic theory of quasibound Laughlin pairs using the physical two-electron Hamiltonian. For a general local electric-field gradient, we determine the dissociation threshold, number of quasibound states, and decay rates. Complex scaling and analytic tunneling theory show that lifetimes grow exponentially with pair energy above threshold. Applied to reported GaAs parameters, the theory indicates that existing devices may already support the lowest spin-polarized pair, with a lifetime estimate roughly two orders of magnitude longer than typical propagation times. We simulate a collision with the full finite-field Hamiltonian, providing both a framework for nonlinear two-electron quantum dynamics and evidence for Laughlin-pair formation in a representative two-electron collision. We use Husimi distributions and their zeros to visualize both quasibound resonances and transient collision states in phase space. These results place the preparation, propagation, and detection of repulsively paired electrons within reach of existing single-electron circuit technology. They identify kinematic stabilization under constrained one-dimensional propagation as a pairing mechanism that may extend to anyonic quantum Hall edge excitations.

cond-mat.mes-hall