YBa2Cu3O7 as a high-temperature superinductor

Abstract

The magnetic behaviour of type-II superconductors is explained by a quantum vortex with a supercurrent encircling a coherence-length-sized core. In a superconducting film with a thickness of t < λ_L, the vortex field decays slowly as 1/r², extending to the Pearl length \({P}_{{\rm{L}}}=\frac{2{\lambda }_{{\rm{L}}}^{2}}{t}\), known as the Pearl vortex, rather than diverging as log[1/r] and decaying with London penetration depth λ_L, as that in the Abrikosov vortex. However, the effect of the Pearl vortex on a large enhancement in the kinetic inductance has not been fully explored. Here we discovered Pearl inductance, an additional form of kinetic inductance arising from geometrical structuring of high-superconducting-transition-temperature (T_c) YBCO superconductor thin films at the Pearl length scale. This results from an extension of vortex screening supercurrents from λ_L to 14λ_L in an ultrathin metamaterial resonator of thickness λ_L/7, enabling terahertz superinductance. Our device shows impedance exceeding the quantum resistance limit R_Q = 6.47 kΩ by 33%, offering possibilities for cutting-edge electronic, photonic and quantum devices.