Probing the Anisotropic Fermi Surface in Tetralayer Graphene via Transverse Magnetic Focusing

Abstract

Bernal-stacked tetralayer graphene (4LG) exhibits intriguing low-energy properties, featuring two massive subbands and showcasing diverse features of topologically distinct, anisotropic Fermi surfaces, including Lifshitz transitions and trigonal warping. Here, we study the influence of the band structure on electron dynamics within 4LG using transverse magnetic focusing. Our analysis reveals two distinct focusing peaks corresponding to the two subbands. Furthermore, we uncover a pronounced dependence of the focusing spectra on crystal orientations, indicative of an anisotropic Fermi surface. Utilizing the semiclassical model, we attribute this orientation-dependent behavior to the trigonal warping of the band structure. This phenomenon leads to variations in electron trajectories based on crystal orientation. Our findings not only enhance our understanding of the dynamics of electrons in 4LG, but also offer a promising method for probing anisotropic Fermi surfaces in other materials.

12 pages, 7 figures

References in corpus (10)

• Micrometer-scale ballistic transport in encapsulated graphene at room temperature
• The electronic properties of bilayer graphene
• Quantum Hall effect and Landau level crossing of Dirac fermions in trilayer graphene
• Quantum cascade of new correlated phases in trigonally warped bilayer graphene
• Charge accumulation at the boundaries of a graphene strip induced by a gate voltage: Electrostatic approach
• Controlled spatial separation of spins and coherent dynamics in spin-orbit-coupled nanostructures
• Ballistic transport spectroscopy of spin-orbit-coupled bands in monolayer graphene on WSe${}_2$
• Specular electron focusing between gate-defined quantum point contacts in bilayer graphene
• Influence of device geometry and imperfections on the interpretation of transverse magnetic focusing experiments
• Magnetoconductance Oscillations in Electron-hole Hybridization Gaps and Valley Splittings in Tetralayer Graphene