Quantum stabilizers implemented with superconducting hardware

Quantum stabilizer operations play an important role in quantum error correction and are typically implemented in software-controlled entangling gates and measurements of groups of qubits. Alternatively, qubits can be designed so that the Hamiltonian includes terms that corresponds directly to stabilizers for protecting quantum information. In this talk, we demonstrate such a hardware implementation of stabilizers in a superconducting circuit based on concatenation of π-periodic Josephson elements. With local on-chip flux- and charge-biasing, we observe a flattening of the transition between the computational states with respect to flux that is exponential in the number of frustrated plaquette elements, in close agreement with our numerical modeling.