Structural Instability of Driven Josephson Circuits Prevented by an Inductive Shunt
Lucas Verney, Raphaël Lescanne, Michel Devoret, Zaki Leghtas, Mazyar Mirrahimi · Physical Review Applied · 2019
Strongly driven superconducting circuits are a versatile platform to implement a multitude of Hamiltonians for quantum computation, simulation, and sensing. Unfortunately, they can display complex dynamics with instabilities, so predicting and preventing these instabilities is crucial for applications. This paper proposes an inductively shunted transmon qubit as the elementary circuit optimized for strong parametric drives. Developing a numerical approach that avoids the limitations of perturbative analysis, the authors demonstrate that adding the inductive shunt significantly extends the range of pump powers in which the circuit is stable.