Meissner Effect and Nonreciprocal Charge Transport in Superconducting 1T-CrTe2/FeTe Heterostructures

Abstract: Interface-induced superconductivity has recently been achieved by stacking a magnetic topological insulator layer on an antiferromagnetic FeTe layer. However, the mechanism driving this emergent superconductivity remains unclear. Here, we employ molecular beam epitaxy to grow a 1T-CrTe2 layer, a two-dimensional ferromagnet with Curie temperature up to room temperature, on a FeTe layer. These 1T-CrTe2/FeTe heterostructures show superconductivity with a critical temperature of ~12 K. Through magnetic force microscopy measurements, we observe the Meissner effect on the surface of the 1T-CrTe2 layer. Our electrical transport measurements reveal that the 1T-CrTe2/FeTe heterostructures exhibit nonreciprocal charge transport behavior, characterized by a large magneto-chiral anisotropy coefficient. The enhanced nonreciprocal charge transport in 1T-CrTe2/FeTe heterostructures provides a promising platform for exploring the magnetically controllable superconducting diode effect.