Nanowire Superinductors
Licentiatavhandling, 2018

In this thesis, we demonstrate that a disordered superconductor with a high kinetic inductance can realize a low microwave loss, non-dissipative circuit element with an impedance greater than the quantum resistance (Rq = h/4e^2 = 6.5kΩ). This element, known as a superinductor, can produce a quantum circuit where charge fluctuations are suppressed.

We have fabricated and characterized 20nm thick niobium-nitride nanowires with a width of 40nm, implementing a superinductance with impedance Z = 6.795kΩ. We demonstrate internal quality factors Qi = 2.5×10^4 at single photon excitation, which is significantly higher than values reported in devices with similar materials and geometries. Moreover, we show that the dominant dissipation in our nanowires is not an intrinsic property of the disordered films, but can instead be fully understood within the well-studied framework of two-level systems.

Disordered Superconductors

Superinductance

Superinductor

Resonator

Nanowire

TLS

Författare

David Niepce

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Superinduktans för långlivad kvantkoherens

Chalmers, 2013-10-01 -- 2014-06-30.

Styrkeområden

Nanovetenskap och nanoteknik

Ämneskategorier

Annan fysik

Annan elektroteknik och elektronik

Den kondenserade materiens fysik

Infrastruktur

Nanotekniklaboratoriet

Technical report MC2 - Department of Microtechnology and Nanoscience, Chalmers University of Technology: MC2-392

Utgivare

Chalmers tekniska högskola

Mer information

Senast uppdaterat

2018-08-15