Boosting Superconducting Electronics with the Josephson Effect

This is the first recording of the Superconductivity Talks webinar series hosted by the Young Professionals committee of the IEEE Council of Superconductivity. Dr. Halima Ahmad will speak about her research with superconducting quantum circuits.

Since its first discovery in the early ‘60s, the Josephson effect has been a powerful tool to study the fundamental physics occurring in conventional and unconventional superconducting materials and the exotic phenomena arising when coupling superconductors with barriers far from simple insulators or metals [1]. However, Josephson junctions are not just a laboratory platform. The research community has already demonstrated that they can enhance the capabilities of superconducting electronics in real-world applications: from highly sensitive magnetometry to quantum metrology and from quantum detection to quantum computation [2]. In this talk, we will specifically focus on the possibility of building a hybrid classical/quantum superconducting platform for high-performance computing by exploiting unconventional Josephson junctions that use ferromagnetic tunnel barriers (tunnel-SFS JJs) [3-7]. Tunnel SFS JJs have the potential of enlarging the capabilities of current state-of-the-art superconducting electronics [8-12]. The high quality of tunnel JJs adds to the chance to tune the magnetization of the ferromagnetic barrier. We show that this allows setting up a convenient playground for novel control, read-out, and memorization mechanisms. [1] A. Barone and G. Paternò, John Wiley & Sons, Inc. 9780471014690 (1982). [2] F. Tafuri, Vol. 286. Springer Nature, (2019). [3] K. Senapati, et al., Nature Materials, 849 (2011). [4] A. Pal, et al., Nature Communications, 3340 (2014). [5] R. Caruso, et al., Phys. Rev. Lett. 122, 047002 (2019). [6] R. Satariano, et al., Phys. Rev. B 103, 224521 (2020). [7] Ahmad, H. G., et al., arXiv preprint arXiv:2106.15646 (2021). [8] D. Massarotti, et al., Nature Communications, 7376 (2015). [9] H.G. Ahmad, et al., Phys. Rev. Applied 13, 014017 (2020). [10] R. Caruso, et al., Journal of Applied Physics, 123 (2018). [11] Loredana Parlato, et al., Journal of Applied Physics 127, 193901 (2020). [12] H.G. Ahmad et al., submitted paper (2021).