High Kinetic Inductance Nb N Nanowire Superinductors

Artikel i vetenskaplig tidskrift, 2019

We demonstrate that a high kinetic inductance disordered-superconductor nanowire can realize a circuit element - known as a superinductor - with a characteristic impedance greater than the quantum resistance (RQ=h/4e2≃6.5kΩ) and a quality factor of 25 000 at single-photon excitation. By examining loss rates, we demonstrate that the microwave dissipation can be fully understood in the framework of two-level-system dielectric loss. Superinductors can suppress the quantum fluctuations of charge in a circuit, which has applications, for example, in devices for quantum computing, photon detection, and other sensors based on mesoscopic circuits.