Controlling magnetism through Ising superconductivity in magnetic van der Waals heterostructures

Abstract

Van der Waals heterostructures have risen as a tunable platform to combine different electronic orders, due to the flexibility in stacking different materials with competing symmetry broken states. Among them, van der Waals ferromagnets such as CrI 3 , CrBr 3 , or CrCl 3 and superconductors as NbSe 2 provide a natural platform to engineer novel phenomena at ferromagnet-superconductor interfaces. In particular, NbSe 2 is well known for hosting strong spin-orbit coupling effects that influence the properties of the superconducting state. Here we put forward a ferromagnet/NbSe 2 /ferromagnet heterostructure where the interplay between Ising superconductivity in NbSe 2 and magnetism controls the magnetic alignment of the heterostructure. In particular, we show that the interplay between spin-orbit coupling and superconductivity provides a new mechanism to control magnetic ordering in van der Waals materials. We show that this coupling allows creating heterostructures featuring a magnetic phase transition from in-plane to out-of-plane associated with the onset of superconductivity. Our results show how a hybrid van der Waals ferromagnet/superconductor heterostructure can be used as a tunable materials platform for superconducting spin-orbitronics.

Superconductor-ferromagnet hybrids for non-reciprocal electronics and detectors

“…Van der Waals stacking of magnetic insulator and superconductor layers, as reported in several recent studies, has produced high-quality samples exhibiting a diverse array of intriguing properties. This showcases the significant potential of this technique [99,100]. Inherently, 2D materials exhibit a sharp interface between adjacent layers in their stacks.…”

“…For example, a rich assortment of strongly correlated electronic states is evident in twisted bilayer graphene [102]. On the other hand, sharp well-defined interfaces between dissimilar 2D materials enable engineering of interface-dependent effects, like exchange splitting of the electronic density of states in the superconductors [100]. For instance, a heterostructure that integrates an insulating layer of the ferromagnetic CrBr 3 and superconducting NbSe 2 showcases these capabilities [99].…”

Neutron Diffraction and Reflectometry: A Review on Unique Role in Functional Magnetic Materials

“…PNR is being successfully used in new emerging functional materials like chiral magnets [71] and topological insulators [72,73] as well as conventional subject like superconductivity [74]. In chiral magnets it is believed that lack of inversion symmetry induces Dzyaloshinski-Moriya interaction leading to chiral spin structure.…”

Magnetic proximity effect in the two-dimensional ε-Fe2O3/NbSe2 heterojunction

“…However, curious phenomena arise in magnet-superconductor heterojunctions, including unconventional superconductivity, topological superconductivity, and the modulation of magnetic alignment by Ising superconductivity. [7][8][9][10][11] Therefore, magnet/superconductor junctions offer a great platform to study the fundamental interaction between superconductivity and magnetism. Moreover, they produce significant opportuni-ties to develop spintronics and superconducting spintronic devices.…”