English

Superconducting Quantum Interference in Twisted van der Waals Heterostructures

Superconductivity 2021-08-18 v1 Mesoscale and Nanoscale Physics

Abstract

Modern Superconducting QUantum Interference Devices (SQUIDs) are commonly fabricated from either Al or Nb electrodes, with an in-situ oxidation process to create a weak link between them. However, common problems of such planar nano- and micro-SQUIDs are hysteretic current-voltage curves, and a shallow flux modulation depth. Here, we demonstrate the formation of both Josephson junctions and SQUIDs using a dry transfer technique to stack and deterministically misalign flakes of NbSe2_{2}; allowing one to overcome these issues. The Josephson dynamics of the resulting twisted NbSe2_{2}-NbSe2_{2} junctions are found to be sensitive to the misalignment angle of the crystallographic axes. A single lithographic process was then implemented to shape the Josephson junction into a SQUID geometry with typical loop areas of \simeq 25 μm2\mu m^{2} and weak links \simeq 600 nm wide. These devices display large stable current and voltage modulation depths of up to ΔIc\Delta I_{c} \simeq 75%\% and ΔV\Delta V \simeq 1.4 mV respectively.

Keywords

Cite

@article{arxiv.2101.04557,
  title  = {Superconducting Quantum Interference in Twisted van der Waals Heterostructures},
  author = {Liam S. Farrar and Aimee Nevill and Zhen Jieh Lim and Geetha Balakrishnan and Sara Dale and Simon J. Bending},
  journal= {arXiv preprint arXiv:2101.04557},
  year   = {2021}
}

Comments

12 pages, 6 figures

R2 v1 2026-06-23T22:04:31.680Z