Unconventional superconducting states are unique states of superconductivity that arise from physical processes that deviate from the traditional Bardeen, Cooper, and Schrieffer (BCS) theory. These states are characterized by the intricate interplay between magnetism and superconductivity.
Ziji Xiang, a co-author of a recent paper from USTC, delved into the unconventional superconductivity found at the interface between (110)-oriented KTaO3 (KTO) and ferromagnetic EuO. Despite KTO and EuO being insulators, their interface in a heterostructure harbors a two-dimensional electron gas (2DEG) that exhibits superconductivity at low temperatures.
The primary goals of the researchers in this study were to uncover new superconducting states in an oxide heterostructure with a ferromagnetic layer (EuO) and to investigate how interface superconductivity evolves under experimental manipulations, such as altering the carrier density (ns) at the interface.
Xiang explained, “Our research is motivated by the fact that unconventional superconductivity often emerges in the presence of magnetism. For instance, in high-temperature superconductors based on copper and iron, many proposed pairing mechanisms are linked to magnetism. The interaction between magnetism and superconductivity can lead to the emergence of unique phases of matter, such as pair-density-wave (PDW) order and finite-momentum pairing.”
The EuO/KTO heterostructure studied by Xiang and his team displays a robust ferromagnetic proximity effect induced by the EuO layer, making it an excellent platform for investigating unconventional superconductivity.
2024-04-08 23:51:01
Source from phys.org