The field-free Josephson diode in a van der Waals heterostructure

Heng Wu*, Yaojia Wang, Yuanfeng Xu, Pranava K. Sivakumar, Chris Pasco, Ulderico Filippozzi, Stuart S.P. Parkin, Yu Jia Zeng, Tyrel McQueen, Mazhar N. Ali

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

Abstract

The superconducting analogue to the semiconducting diode, the Josephson diode, has long been sought with multiple avenues to realization being proposed by theorists1–3. Showing magnetic-field-free, single-directional superconductivity with Josephson coupling, it would serve as the building block for next-generation superconducting circuit technology. Here we realized the Josephson diode by fabricating an inversion symmetry breaking van der Waals heterostructure of NbSe2/Nb3Br8/NbSe2. We demonstrate that even without a magnetic field, the junction can be superconducting with a positive current while being resistive with a negative current. The ΔIc behaviour (the difference between positive and negative critical currents) with magnetic field is symmetric and Josephson coupling is proved through the Fraunhofer pattern. Also, stable half-wave rectification of a square-wave excitation was achieved with a very low switching current density, high rectification ratio and high robustness. This non-reciprocal behaviour strongly violates the known Josephson relations and opens the door to discover new mechanisms and physical phenomena through integration of quantum materials with Josephson junctions, and provides new avenues for superconducting quantum devices.

Original languageEnglish
Pages (from-to)653-656
JournalNature
Volume604
Issue number7907
DOIs
Publication statusPublished - 2022

Fingerprint

Dive into the research topics of 'The field-free Josephson diode in a van der Waals heterostructure'. Together they form a unique fingerprint.

Cite this