We develop a fast Magnetic Josephson Junction (MJJ) - a superconducting ferromagnetic device for a scalable high-density cryogenic memory compatible in speed and fabrication with energy-efficient Single Flux Quantum (SFQ) circuits. We present experimental results for Superconductor-Insulator-Ferromagnet-Superconductor (SIFS) MJJs with high characteristic voltage IcRn of >700 uV proving their applicability for superconducting circuits. By applying magnetic field pulses, the device can be switched between MJJ logic states. The MJJ IcRn product is only ~30% lower than that of conventional junction co-produced in the same process, allowing for integration of MJJ-based and SIS-based ultra-fast digital SFQ circuits operating at tens of gigahertz.
@article{arxiv.1205.3372,
title = {Ferromagnetic Josephson switching device with high characteristic voltage},
author = {T. I. Larkin and V. V. Bol'ginov and V. S. Stolyarov and V. V. Ryazanov and I. V. Vernik and S. K. Tolpygo and O. A. Mukhanov},
journal= {arXiv preprint arXiv:1205.3372},
year = {2012}
}