On-Chip Integrable Planar NbN NanoSQUID with Broad Temperature and Magnetic-Field Operation Range

TL;DR

This paper presents a novel on-chip NbN nanoSQUID with broad temperature and magnetic field operation, demonstrating its potential for scalable quantum and electro-optical applications.

Contribution

A single-lithography NbN nanoSQUID with broad operational ranges and scalable fabrication process is introduced, enabling advanced on-chip quantum and sensing technologies.

Findings

Operates from 20 mK to 5 K temperature range

Functions in magnetic fields up to 10 mT perpendicular and 1 T parallel

Potential for operation above 8 T magnetic field

Abstract

Superconducting quantum interference devices (SQUIDs) are used for applications ranging from sensitive magnetometers to low-temperature electronics and quantum computation. We introduce a planar nano SQUID that was made with a single lithographic step out of NbN films as thin as 3 nm on a Si chip. The fabrication process of weak links that are 45 nm in width, and 165 nm in length, which were designed to account for overcoming current crowding are presented. Operation at a temperature range of 20 mK to 5 K as well as at 1 T parallel, and 10 mT perpendicular magnetic fields is demonstrated, while potential operation higher than 8 T has also been shown. The broad range of applicability of a single device as well as its scalability are promising for on-chip integrability that may open new technological possibilities, including in quantum and electro-optical circuiting.