Transport Anisotropy in One-dimensional Graphene Superlattice in the High Kronig-Penney Potential Limit

Abstract

One-dimensional graphene superlattice subjected to strong Kronig-Penney (KP) potential is promising for achieving electron lensing effect, while previous studies utilizing the modulated dielectric gates can only yield a moderate, spatially dispersed potential profile. Here, we realize high KP potential modulation of graphene via nanoscale ferroelectric domain gating. Graphene transistors are fabricated on PbZr${}_{0.2}$Ti${}_{0.8}$O${}_3$ back-gates patterned with periodic, 100-200 nm wide stripe domains. Due to band reconstruction, the h-BN top-gating induces satellite Dirac points in samples with current along the superlattice vector $\hat{s}$, a feature absent in samples with current perpendicular to $\hat{s}$. The satellite Dirac point position scales with the superlattice period ($L$) as $\propto L^{\beta }$, with $\beta =-1.18\pm 0.06$. These results can be well explained by the high KP potential scenario, with the Fermi velocity perpendicular to $\hat{s}$ quenched to about 1% of that for pristine graphene. Our study presents a promising material platform for realizing electron supercollimation and investigating flat band phenomena.

12 pages, 5 figures, and Supplemental Material

References in corpus (11)

• Anisotropic behaviors of massless Dirac fermions in graphene under periodic potential
• New Generation of Massless Dirac Fermions in Graphene under External Periodic Potentials
• Electron Beam Supercollimation in Graphene Superlattices
• Gate-controlled non-volatile graphene-ferroelectric memory
• Landau Levels and Quantum Hall Effect in Graphene Superlattices
• Programming Correlated Magnetic States via Gate Controlled Moiré Geometry
• Dry release transfer of graphene and few-layer h-BN by utilizing thermoplasticity of polypropylene carbonate for fabricating edge-contact-free van der Waals heterostructures
• Superlattices based on van der Waals 2D materials
• Electron supercollimation in graphene and Dirac fermion materials using one-dimensional disorder potentials
• Two-dimensional Dirac fermions in a mass superlattice
• Remote Surface Optical Phonon Scattering in Ferroelectric Ba${}_{0.6}$Sr${}_{0.4}$TiO${}_3$ Gated Graphene

Cited by in corpus (6)

• Anisotropic effects in two-dimensional materials
• Understanding Disorder in Monolayer Graphene Devices with Gate-Defined Superlattices
• Nanoscale ferroelectric programming of van der Waals heterostructures
• Relativistic particles in super-periodic potentials: exploring graphene and fractal systems
• One-dimensional Lieb superlattices: from the discrete to the continuum limit
• Magnetic Bloch bands and Weiss oscillations in Dirac mass superlattices