Colloidal topological insulators

Abstract

Topological insulators insulate in the bulk but exhibit robust conducting edge states protected by the topology of the bulk material. Here, we design a colloidal topological insulator and demonstrate experimentally the occurrence of edge states in a classical particle system. Magnetic colloidal particles travel along the edge of two distinct magnetic lattices. We drive the colloids with a uniform external magnetic field that performs a topologically non-trivial modulation loop. The loop induces closed orbits in the bulk of the magnetic lattices. At the edge, where both lattices merge, the colloids perform skipping orbits trajectories and hence edge-transport. We also observe paramagnetic and diamagnetic colloids moving in opposite directions along the edge between two inverted patterns; the analogue of a quantum spin Hall effect in topological insulators. We present a new, robust, and versatile way of transporting colloidal particles, enabling new pathways towards lab on a chip applications.

References in corpus (5)

• Topological modes bound to dislocations in mechanical metamaterials
• Topological colloids
• Topological Quantum Optics in Two-Dimensional Atomic Arrays
• Lattice symmetries and the topological protected transport of colloidal particles
• Topologically protected colloidal transport above a square magnetic lattice

Cited by in corpus (21)

• Power functional theory for many-body dynamics
• Noether's Theorem in Statistical Mechanics
• Reversibility, Pattern Formation and Edge Transport in Active Chiral and Passive Disk Mixtures
• Ice Rule Fragility via Topological Charge Transfer in Artificial Colloidal Ice
• Confining massless Dirac particles in two-dimensional curved space
• Magnetic domains without domain walls: a unique effect of He+ ion bombardment in ferrimagnetic Co/Tb multilayers
• Dynamics of Magnus Dominated Particle Clusters, Collisions, Pinning and Ratchets
• Guided Skyrmion Motion Along Pinning Array Interfaces
• Shear Banding, Intermittency, Jamming and Dynamic Phases for Skyrmions in Inhomogeneous Pinning Arrays
• Edge states at the boundary between topologically equivalent lattices
• Skyrmion Dynamics and Transverse Mobility: Skyrmion Hall Angle Reversal on 2D Periodic Substrates with dc and Biharmonic ac Drives
• Skyrmion Pinball and Directed Motion on Obstacle Arrays
• Topologically controlled synthesis of active colloidal bipeds
• Chiral Edge Currents for ac Driven Skyrmions in Confined Pinning Geometries
• Disorder scattering in classical flat channel transport of particles between twisted magnetic square patterns
• Topologically cloaked magnetic colloidal transport
• Topological Order in Densely Packed Anisotropic Colloids
• Topological sorting of magnetic colloidal bipeds
• Hybridization of colloidal handlebodies with singular defects and topological solitons in chiral liquid crystals
• Adiabatic and irreversible classical discrete time crystals
• Magnetic colloidal single particles and dumbbells on a tilted washboard moire pattern in a precessing external field