Inverse flux quantum periodicity of magnetoresistance oscillations in two-dimensional short-period surface superlattices

Abstract

Transport properties of the two-dimensional electron gas (2DEG) are considered in the presence of a perpendicular magnetic field $B$ and of a {\it weak} two-dimensional (2D) periodic potential modulation in the 2DEG plane. The symmetry of the latter is rectangular or hexagonal. The well-known solution of the corresponding tight-binding equation shows that each Landau level splits into several subbands when a rational number of flux quanta $h/e$ pierces the unit cell and that the corresponding gaps are exponentially small. Assuming the latter are closed due to disorder gives analytical wave functions and simplifies considerably the evaluation of the magnetoresistivity tensor ${\rho }_{\mu \nu }$. The relative phase of the oscillations in ${\rho }_{xx}$ and ${\rho }_{yy}$ depends on the modulation periods involved. For a 2D modulation with a {\bf short} period $\le 100$ nm, in addition to the Weiss oscillations the collisional contribution to the conductivity and consequently the tensor ${\rho }_{\mu \nu }$ show {\it prominent peaks when one flux quantum $h/e$ passes through an integral number of unit cells} in good agreement with recent experiments. For periods $300-400$ nm long used in early experiments, these peaks occur at fields 10-25 times smaller than those of the Weiss oscillations and are not resolved.

References in corpus (2)

• Magnetoresistance calculations for a two-dimensional electron gas with unilateral short-period strong modulation
• Magnetic Miniband Structure and Quantum Oscillations in Lateral Semiconductor Superlattices

Cited by in corpus (6)

• From laterally modulated two-dimensional electron gas towards artificial graphene
• Geometric resonances in the magnetoresistance of hexagonal lateral superlattices
• Emergent flat band lattices in spatially periodic magnetic fields
• Localized Wavefunctions and Magnetic Band Structure for Lateral Semiconductor Superlattices
• Suppression of Weiss oscillations in the magnetoconductivity of modulated graphene monolayer
• Beats of the Magnetocapacitance Oscillations in Lateral Semiconductor Superlattices