Simulating kaon mixing with Josephson phase qubits

Superconducting circuits with Josephson junctions distinguish themselves from other types of quantum computing architectures by having easily controllable metastable computational states (the so-called phase qubits) with a very large ratio of their respective lifetimes. In this pedagogical note I describe how we can use this remarkable property of the phase qubits to further test the validity of the superposition principle in the macroscopic quantum regime by simulating the kaon mixing mechanism of particle physics.