The semiconducting diode, which is characterized by a highly asymmetric current-voltage relation, is central to modern-day electronics. In the last few years, its superconducting analogue – a system that behaves like a superconductor for current flow in one direction but exhibits finite resistance when the current direction is reversed – has attracted attention in the physics community, due to its potential for future quantum-electronics applications. So far, this behavior has only been realized in the presence of a magnetic field, magnetic junction or magnetic proximity, and is typically rather weak in the sense that it exhibits the superconducting diode effect only for a small range of applied current.
In this talk, I will present experimental evidence and a microscopic theory for a strong superconducting diode effect at zero external magnetic in twisted trilayer graphene [1-3]. After a brief introduction to the rich physics of twisted trilayer graphene close to the magic angle, I will discuss why this is a natural system to realize this exotic superconducting behavior as an intrinsic property and illustrate the intricate underlying microscopic physics.
 Siriviboon, Lin, Scammell, Liu, Rhodes, Watanabe, Taniguchi, Hone, MS, Li, arXiv:2112.09115.
 Lin, Siriviboon, Scammell, Liu, Rhodes, Watanabe, Taniguchi, Hone, MS, Li, and arXiv:2212.07841.
 Scammell, Li, MS, arXiv:2112.09115.