Superconducting Quantum Interference in Twisted van der Waals Heterostructures.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 34428907.
- Also identified by DOI 10.1021/acs.nanolett.1c00152 and PMC identifier 8397396.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
We demonstrate the formation of both Josephson junctions and superconducting quantum interference devices (SQUIDs) using a dry transfer technique to stack and deterministically misalign mechanically exfoliated flakes of NbSe<sub>2</sub>. The current-voltage characteristics of the resulting twisted NbSe<sub>2</sub>-NbSe<sub>2</sub> junctions are found to be sensitive to the misalignment angle of the crystallographic axes, opening up a new control parameter for optimization of the device performance, which is not available in thin-film-deposited junctions. A single lithographic process has then been implemented to shape Josephson junctions into SQUID geometries with typical loop areas of ∼25 μm<sup>2</sup> and weak links ∼600 nm wide. At <i>T</i> = 3.75 K in an applied magnetic field, these devices display large stable current and voltage modulation depths of up to Δ<i>I</i><sub>c</sub> ∼ 75% and Δ<i>V</i> ∼ 1.4 mV, respectively.