Honeycomb qubit lattice could allow all-to-all qubit connections

Researchers at IQM Quantum Computers have designed a honeycomb qubit lattice enabling all-to-all connectivity between qubits within a unit cell, a departure from more limited connections in existing superconducting quantum computer architectures. The work addresses key challenges in scaling quantum computers by simultaneously increasing connectivity and reducing qubit-state delocalization. The team proposes a novel conditional-Z gate scheme implemented in a single step, which they state “considerably improves the gate speed” compared to previous designs. This multi-mode coupling structure also mitigates crosstalk during simultaneous single-qubit gates. This design achieves full connectivity by coupling each qubit to every other one via two dedicated tunable couplers and a shared central element, creating an effective multi-mode interaction. The lattice’s structure allows for a novel conditional-Z gate…