High-efficiency superconducting diodes: critical phenomena and universal digital logic

Recent advancements in the realizations of superconducting diodes have pushed the diode coefficient η towards its theoretical maximum of η=1 in several platforms, yet the fundamental ingredients for high diode efficiency remain mysterious. In this work, we first show that in intrinsic superconducting diodes, a perfect diode with η=1 necessarily requires fine-tuning to a phase transition. We then describe the construction of logic gates NOT, AND, OR, NAND and NOR using superconducting diodes with η≈1 by exploiting their dynamically tunable polarity. Thus, this work provides guiding principles towards future platforms and building blocks for superconductors-based digital electronics.