Figure 1: Schematic representation of topologically protected state transfer.

The grey droplet represents a 2D array of interacting qubits (spins or pseudo-spins) tuned into the CSLB phase. Quantum registers composed of a transfer qubit (green) and a memory qubit (gold) are arranged around the edge of the 2D droplet and coupling between them occurs through the chiral edge mode. (1) By mapping the quantum information onto a fermionic wavepacket (blue) travelling along the edge, the quantum state can be transferred to a remote register. The wavepacket travels only in the direction of the blue arrow; this chirality prevents mode localization and destructive backscattering. At a specified time at the remote register location, the coupling is turned on and the wavepacket is captured (2). Given an ancillary memory qubit and local register manipulations, a two-qubit gate (3) can be performed before the quantum state is transferred back to the original register and stored (4–5). This allows for universal computation between the memory qubits of spatially separated registers.