High‐T _c Superinductors Through Tailored Metamaterial Losses

Abstract Superinductance, with impedance surpassing the quantum resistance of 6.47 kΩ, has recently been discovered in high‐temperature superconducting terahertz metamaterials, enabling advancement in quantum computing and high‐frequency electronics. Superconducting Cooper pairs enable low‐loss kinetic inductance, a crucial factor in achieving superinductance. However, sustaining this effect at terahertz frequencies is hindered by increasing ohmic losses, necessitating a deeper understanding of dissipation mechanisms. In this study, radiative and ohmic losses are systematically analyzed in metamaterial LC resonators fabricated with 25 and 50 nm YBa ₂ Cu ₃ O _7‐δ films. Using a Lorentzian fitting function derived from coupled‐mode theory, a parametric loss model linking radiative losses is established to film conductivity, providing design principles for optimized superconducting metamaterials with sustained superinductance. This work lays the foundation for scalable metamaterial superinductor design, advancing quantum computing, kinetic inductance detectors, and terahertz high‐temperature superconductor based single photon detectors.