Superconducting resonators with high kinetic inductance play a central role in hybrid quantum circuits, enabling strong coupling to systems with small electric dipole moment and providing the nonlinear response required for parametric amplification. However, simultaneously achieving these resonators with high internal quality factors ($Q_i$) and resilience to strong magnetic fields remains challenging. In this work, we present a systematic and quantitative comparison between niobium nitride ($\mathrm{Nb}\mathrm{N}$) and granular aluminum (grAl) nanowire resonators, two widely used high-kinetic-inductance superconductors that offer complementary properties in terms of magnetic robustness and intrinsic nonlinearity. The devices are fabricated to exhibit comparable sheet kinetic inductance ($L_k\sim 100$ pH/sq), to allow a direct assessment of material-dependent behavior under identical experimental conditions. At zero magnetic field, grAl resonators display higher $Q_i$ compared with their $\mathrm{Nb}\mathrm{N}$ counterparts, whereas under applied magnetic fields, $\mathrm{Nb}\mathrm{N}$ resonators demonstrate significantly better resilience, maintaining $Q_i>{10}^4$ up to several tesla. A nonmonotonic enhancement of $Q_i$ in $\mathrm{Nb}\mathrm{N}$ near 1 T is observed, providing new insight into dissipation mechanisms in disordered superconductors. In contrast, grAl resonators show monotonic $Q_i$ evolution and a distinct critical field above which $Q_i$ rapidly decreases. Characterization of nonlinear properties at zero magnetic field reveals that the self-Kerr coefficient in grAl is more than an order of magnitude higher than in $\mathrm{Nb}\mathrm{N}$, making grAl particularly attractive for applications requiring pronounced nonlinear interactions. This comparative study clarifies how microscopic disorder and superconducting energy scales influence field resilience and nonlinearity in high-$L_k$ materials providing practical guidelines for designing magnetic-field compatible, high-impedance resonators for hybrid quantum circuits.

Close

PrevNext

View figure in article

• High magnetic fields
• Quantum engineering
• Quantum harmonic oscillator
• Quantum information processing
• Superconducting RF
• Low-temperature superconductors
• Superconducting devices
• Thin films