Non-Majorana origin of anomalous current-phase relation and Josephson diode effect in Bi 2 Se 3 /NbSe 2 Josephson junctions

Andrei Kudriashov; Xiangyu Zhou; Razmik A. Hovhannisyan; Alexander S. Frolov; Leonid Elesin; Yi Bo Wang; Ekaterina V. Zharkova; Takashi Taniguchi; Kenji Watanabe; Zheng Liu; Kostya S. Novoselov; Lada V. Yashina; Xin Zhou; Denis A. Bandurin

doi:10.1126/sciadv.adw6925

Journal article Non-Majorana origin of anomalous current-phase relation and Josephson diode effect in Bi ₂ Se ₃ /NbSe ₂ Josephson junctions

; ; ; ; ; ; ;

;

; ; ; ; ;

Download file (3.64 MB)
Download as zip (3.39 MB)

Collection

Citation

Andrei Kudriashov, Xiangyu Zhou, Razmik A. Hovhannisyan, Alexander S. Frolov, Leonid Elesin, Yi Bo Wang, Ekaterina V. Zharkova, Takashi Taniguchi, Kenji Watanabe, Zheng Liu, Kostya S. Novoselov, Lada V. Yashina, Xin Zhou, Denis A. Bandurin. Non-Majorana origin of anomalous current-phase relation and Josephson diode effect in Bi ₂ Se ₃ /NbSe ₂ Josephson junctions. Science Advances. 2025, 11 (24), eadw6925. https://doi.org/10.1126/sciadv.adw6925

(BibTeX)

Description:

(abstract)

Josephson junctions (JJs) are key to superconducting quantum technologies and the search for self- conjugate quasiparticles potentially useful for fault- tolerant quantum computing. In topological insulator (TI)–based JJs, measuring the current- phase relation (CPR) can reveal unconventional effects such as Majorana bound states (MBS) and nonreciprocal transport. However, reconstructing CPR as a function of magnetic field has not been attempted. Here, we present a platform for field- dependent CPR measurements in planar JJs made of NbSe2 and few- layer Bi2Se3. When a flux quantum Φ0 threads the junction, we observe anomalous peak- dip CPR structure and nonreciprocal supercurrent flow. We show that these arise from a nonuniform supercurrent distribution that also leads to a robust and tunable Josephson diode effect. Furthermore, despite numerous previous studies, we find no evidence of MBS. Our results establish magnetic field–dependent CPR as a powerful probe of TI- based superconducting devices and offer design strategies for nonreciprocal superconducting electronics.

Rights: