Diamond Circuits for Surface Codes
Abstract
This short paper describes a new circuit to measure surface codes, which allows them to be implemented on the heavy-square lattice. The circuits perform far worse than the usual surface code, but are more efficient in terms of the distance they can achieve for a given number of qubits and couplers.
Paper Abstract:
We present and benchmark an interesting subfamily of circuits within the LUCI framework, which we refer to as diamond circuits, that implement a surface code on a Lieb or “Heavy-Square” lattice. This makes them more qubit- and measurement-efficient than previous constructions. These circuits are built around a mid-cycle state that resembles a Bravyi-Bacon-Shor surface code on the data and measurement qubits. These circuits preserve the spacelike distance of the code, but suffer a penalty in timelike distance. This could be useful in regimes where quantum computers are limited by the number of control lines or frequency collisions.
Paper Abstract:
We present and benchmark an interesting subfamily of circuits within the LUCI framework, which we refer to as diamond circuits, that implement a surface code on a Lieb or “Heavy-Square” lattice. This makes them more qubit- and measurement-efficient than previous constructions. These circuits are built around a mid-cycle state that resembles a Bravyi-Bacon-Shor surface code on the data and measurement qubits. These circuits preserve the spacelike distance of the code, but suffer a penalty in timelike distance. This could be useful in regimes where quantum computers are limited by the number of control lines or frequency collisions.
