Practical Quantum Error Correction with Surface-Cats

In quantum error correction, fault-tolerant circuits limit the ways in which errors spread in a system and are essential for reliable execution of quantum algorithms using unreliable devices. Unfortunately, fault-tolerance comes at the cost of large resource overheads. In fact, the penalty in the overhead can be so serious that it can suppress potential speedups in many quantum algorithms. Therefore, we need to find ways to achieve fault-tolerance in a hardware-efficient manner. Most of the work towards fault-tolerance relies on generic noise models for qubit operations and is agnostic to realistic errors in specific hardware platforms. In this talk I will show how we can achieve substantial reductions in the overheads for fault-tolerant quantum error correction by exploiting the underlying structure of noise in qubits encoded in bosonic degrees of freedom. I will focus on the planar surface code realized using the bosonic Kerr-cat qubit and present numerical results to demonstrate improvements in the resource requirements for fault-tolerance.