Valley-dependent giant orbital moments and transport features in rhombohedral graphene multilayers

Light-element systems with marginal spin-orbital coupling effect serve as an excellent platform for investigating orbital degrees of freedom and exotic physical behaviors. Here, the authors determine via first-principles calculations the orbital magnetic moments, the orbital Hall effect, and the ordinary magnetoconductivity in gated rhombohedral multilayer graphene sheets. Furthermore, the topological properties can be effectively changed for the broken time-reversal symmetry, induced by Floquet light engineering. The study reveals the remarkable tunability of rhombohedral multilayer graphene in orbitronics, valleytronics, and multiferroic applications.