In this talk, I will discuss the rapidly developing field of nonreciprocal effects in superconducting transport, also known as the superconducting diode effect. The essence of this phenomenon lies in the asymmetry of a system’s properties when a supercurrent flows in opposite directions. Such an effect requires the simultaneous breaking of time-reversal and inversion symmetries. The underlying physical mechanisms can vary significantly, including effects of magnetic (and, more specifically, exchange) fields, spin-orbit interactions, and geometric asymmetry of the system. These effects can lead to nonreciprocal charge transport both in systems homogeneous along the current direction and in Josephson junctions.

BIOGRAPHY
Prof. Yakov Fominov holds two PhDs in Theoretical Physics — one from the Kapitza Institute (Russia, 2003) and another from the University of Twente (Netherlands, 2003) — as well as a Doctor of Physics and Mathematics degree from the Landau Institute (2019). Since 2005, he has been a permanent member of the Landau Institute, where he currently serves as Deputy Director. Since 2023, he has also headed the Chair for Problems in Theoretical Physics (Gor’kov Theory Group) at the Moscow Institute of Physics and Technology. His research focuses on the superconducting proximity effect in hybrid structures (including normal and ferromagnetic metals), the Josephson effect in mesoscopic junctions, odd-frequency superconductivity, and superconducting spin valves.

In this talk, I will discuss quantum states in Kagome lattices with the time reversal symmetry breaking. Both theory and recent experimental progress will be reviewed. A brief review of this type of states will be given for cuprates and Kagome lattice superconductors. We will discuss a specific model to show the existence of loop current states which break the time reversal symmetry as ground states. In particular, we will address the superconducting diode effect can be used to probe such quantum states.

BIOGRAPHY
Prof. Jiang-Ping Hu is currently a researcher and the Deputy Director of the Institute of Physics, Chinese Academy of Sciences. He received his BS from Peking University in 1994, MS from the Institute of Theoretical Physics of the Chinese Academy of Sciences in 1997 and PhD from Stanford University in 2002. His main research interests are theoretical condensed matter physics. He has made seminal contributions to topological physics, high-temperature superconductivity, and strongly correlated electron theory, with more than 280 publications and an H-index of 85. He was selected to be a Fellow of the American Physical Society in 2018, and was awarded the Zhou Peiyuan Prize for Physics in 2019, a New Stone Researcher in 2023.