Signature of charge-3e tunneling in twisted cuprate Josephson junctions

@misc{zhu2026signature,
  title = {{Signature of charge-3e tunneling in twisted cuprate Josephson junctions}},
  author = {Yuying Zhu and Heng Wang and Zechao Wang and Zhiyuan Sun and Qi-Kun Xue and Ding Zhang},
  howpublished = {arXiv},
  year = {2026},
  month = nov,
  doi = {10.48550/arxiv.2611.07708},
  eprint = {2611.07708},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2611.07708},
}

TY  - UNPB
TI  - Signature of charge-3e tunneling in twisted cuprate Josephson junctions
AU  - Yuying Zhu
AU  - Heng Wang
AU  - Zechao Wang
AU  - Zhiyuan Sun
AU  - Qi-Kun Xue
AU  - Ding Zhang
PY  - 2026
DA  - 2026/11/05
PB  - arXiv
DO  - 10.48550/arxiv.2611.07708
UR  - https://arxiv.org/abs/2611.07708
AB  - Cooper pairing is a fundamental aspect of superconductivity and results in charge transport with a basic unit of 2e (e is the electron charge). This basic unit can manifest itself as the denominator in the formula for Shapiro steps of ac Josephson effect-nhf/(2e), where h is the Planck constant, f is the ac frequency and n is an integer. Violation of this standard formula may suggest unconventional physics, such as nhf/4e for charge-4e superconductivity. Here, we report discovery of a new sequence of nhf/3e in twisted cuprate Josephson junctions. The microwave frequency/power, temperature, and current annealing dependences of this exotic sequence consistently point to hf/3e as the unit for Shapiro steps, indicating a Josephson tunneling process involving a trio of electrons (3e). This bunching of an odd number of charges distinguishes itself from well-established superconducting processes, which are carried by composite bosons made of an even number of charges. The unusual observations highlight the important interplay between competing charge orders in twisted bilayer systems.
ER  -