Inductive losses in quantum devices: limitations and perspectives

Inductive elements with various degrees of nonlinearity play a pivotal
role in superconducting quantum devices such as kinetic inductance detectors,
parametric amplifiers and quantum bits. Josephson junction arrays implement almost
perfect compact inductors, with low dissipation and high characteristic impedance,
however, their relatively high nonlinearity and design complexity can be a limiting factor.
Granular Aluminum is a disordered superconducting material that bridges the gap between
Josephson junction arrays and atomically disordered superconductors, such as Niobium
Nitride, Indium Oxide, etc. In this talk I will present the various use cases for granular
Aluminum in superconducting quantum electronics, its limitations and some
perspectives of improvement. I will also make a parallel with Josephson junction arrays
and highlight a striking difference between their inductive losses.