The asymmetric transport in superconductors—superconducting diode effect—promises the realization of novel dissipationless electronic devices. Also, its manifestation is often associated with unconventional physics at play. Here, we report the realization of superconducting diode effect in twisted high-temperature cuprate Josephson junctions [1]. We develop a current pulse technique that can reliably introduce the diode effect in cuprate junctions with a twist angle around 45 degrees. The pulse-controlled superconducting diode effect can work stably at liquid nitrogen temperature, with the highest operation temperature reaching 83 K. By further irradiating such a diode with microwave, we demonstrate that the asymmetric transport can be solely carried by Cooper pairs. It allows for perfect diode efficiency and quantized diode output, paving a step toward the practical application of superconducting diodes. We show that the mechanism of our high-temperature superconducting diode effect is related to trapped vortices in the junctions [1,2]. It offers an alternative explanation to topological superconductivity, which has been theoretically proposed to occur in twisted cuprates [3,4].

[1] H. Wang, Y. Zhu, Z. Bai, Z. Lyu, J. Yang, L. Zhao, X. J. Zhou, Q.-K. Xue, and D. Zhang, Quantum superconducting diode effect with perfect efficiency above liquid-nitrogen temperature, Nat. Phys. 22, 47 (2026).

[2] Y. Zhu, H. Wang, D. Zhang, and Q.-K. Xue, Manipulating fractional Shapiro steps in twisted cuprate Josephson junctions, Natl. Sci. Rev. 13, nwaf569 (2026).

[3] O. Can, et al., High-temperature topological superconductivity in twisted double-layer copper oxides, Nat. Phys. 17, 519 (2021).

[4] S. Y. F. Zhao, et al., Time-reversal symmetry breaking superconductivity between twisted cuprate superconductors, Science 382, 1422 (2023).