Fault-tolerant quantum error correction techniques are designed to protect quantum computers from experimental noise, but they are too resource intensive for existing hardware. We propose a partially fault-tolerant implementation of the [[k+2, k, 2]] quantum error detection code — nicknamed Iceberg code — to protect expressive quantum circuits on existing trapped-ion computers. Experiments on Quantinuum’s 12-qubit H1-2 hardware demonstrate the protection of expressive quantum circuits of up to 8 logical qubits and 256 layers and saturate the logical quantum volume 2^8 of this device.

David Amaro, Senior Research Scientist, Quantinuum