Anomalous Hall Coulomb drag of massive Dirac fermions

Abstract

Dirac fermions are actively investigated, and the discovery of the quantized anomalous Hall effect of massive Dirac fermions has spurred the promise of low-energy electronics. Some materials hosting Dirac fermions are natural platforms for interlayer coherence effects such as Coulomb drag and exciton condensation. Here we determine the role played by the anomalous Hall effect in Coulomb drag in massive Dirac fermion systems. We focus on topological insulator films with out-of plane magnetizations in both the active and passive layers. The transverse response of the active layer is dominated by a topological term arising from the Berry curvature. We show that the topological mechanism does not contribute to Coulomb drag, yet the longitudinal drag force in the passive layer gives rise to a transverse drag current. This anomalous Hall drag current is independent of the activelayer magnetization, a fact that can be verified experimentally. It depends non-monotonically on the passive-layer magnetization, exhibiting a peak that becomes more pronounced at low densities. These findings should stimulate new experiments and quantitative studies of anomalous Hall drag.The past decade has witnessed an energetic exploration of Dirac fermions in materials ranging from graphene [1] to topological insulators [2], transition metal dichalcogenides [3] and Weyl and Dirac semimetals [4][5][6]. Dirac fermions in 2D are described by the Hamiltonian H D = A σ · (k ×ẑ) + M σ z , with σ = (σ x , σ y , σ z ) the usual Pauli matrices, k = (k x , k y ) the 2D wave vector, A stems from the Fermi velocity and M a generic mass term. In the limit M → 0 the quasi-particle dispersion is linear, a feature that has aroused intense interest experimentally [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] and theoretically [22][23][24][25][26][27][28][29][30][31][32][33][34]. These studies have illuminated the considerable potential of Dirac fermions for spintronics, thermoelectricity, magnetoelectronics and topological quantum computing [35].Certain materials hosting Dirac fermions, such as 3D topological insulator (TI) slabs, are inherently two-layer systems naturally exhibiting interlayer coherence effects such as Coulomb drag [36][37][38], in which the charge current in one layer drags a charge current in the adjacent layer through the interlayer electron-electron interactions. Drag geometries are intensively studied experimentally in Dirac fermion systems as part of the search for exciton condensation . The most promising Dirac fermion materials have been magnetic TI slabs, in which a dissipationless quantized anomalous Hall effect has been discovered [69][70][71][72], which has already been harnessed successfully [73], stimulating an intense search for device applications. The time-reversal symmetry breaking required in Hall effects [3,28,[74][75][76][77] gives Dirac fermions a finite mass and results in a non-trivial Berry curvature [3,78,79]. Coulomb drag of massive Dirac fermions is thus directly relevant to ongoing experiments, and...

Weak Localization and Antilocalization in Topological Materials with Impurity Spin-Orbit Interactions

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Electrically induced charge-density waves in a two-dimensional electron liquid: Effects of negative electronic compressibility

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Coulomb Drag of Electron-Electron Interactions in GaAs Bilayer with a Non Homogeneous Dielectric Background

“…We have used a general computational scheme and model to describe non-local transport in interactively coupled double layer systems at low temperature and ballistic regime We don't have any experimental and theoretical data corresponding to our system and compare our results theoretically [2,18,19,24,47,49,61] and experimentally with [29] of similar results based on non-homogeneous dielectric environment where. Present approach is based on the Boltzmann kinetic theory, the route to existing formulation to attain the Eq.…”

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