Superinductance for very long-lived quantum coherence

I will develop a “superinductor” – a very-high kinetic inductance superconducting nanowire of thin-film niobium nitride. Its reactive impedance will exceed the quantum resistance (6.5 kΩ) at microwave frequencies, while being nearly lossless at dc. I shall first make this new component, and then design a new type of superconducting qubit (quantum bit of information) – the “metastable flux qubit” – consisting of a nanoscale Josephson junction (JJ) shunted by a superinductance.

This qubit has a very small transition dipole matrix element between its metastable quantum ground states, and therefore extremely small coupling to any noise sources. This enables a projected energy-relaxation coherence time approaching one second – more than three orders of magnitude better than any existing device. Since decoherence is the worst problem impeding the advancement of quantum-information processing (QIP) technology, the successful realization of this long-lived qubit would represent a breakthrough in superconducting quantum engineering.

Participants

Jonas Bylander (contact)

Forskare vid Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Funding

Chalmers

Funding years 2013–2014

Related Areas of Advance and Infrastructure

Nanoscience and Nanotechnology

Areas of Advance

Nanofabrication Laboratory

Infrastructure

More information

Latest update

2016-07-27