Carla Boix-Constant
2D magnetic materials offer unprecedented opportunities for fundamental and applied research in spintronics and magnonics. Of particular interest is the layered metamagnet CrSBr, a relatively air-stable semiconductor formed by antiferromagnetically-coupled ferromagnetic layers (Tc∼150 K) that can be exfoliated down to the single-layer. In this work, the magneto-transport properties of CrSBr vertical heterostructures in the 2D limit are inspected. The results demonstrate the marked low-dimensional character of the ferromagnetic monolayer, with short-range correlations above Tc and an Ising-type in-plane anisotropy, being the spins spontaneously aligned along the easy axis b below Tc. By applying moderate magnetic fields along a and c axes, a spin-reorientation occurs, leading to a magnetoresistance enhancement at low temperatures. In multilayers, a spin-valve behaviour is observed, with negative magnetoresistance strongly enhanced along the three directions below the critical temperature T*1. Moreover, we fabricate an artificial magnet by twisting 90 degrees two CrSBr ferromagnetic monolayers, thus forming an ‘orthogonally-twisted bilayer’2. The magneto-transport properties reveal multistep spin switching with a magnetic hysteresis opening, which is absent in the pristine case. By tuning the magnetic field, we modulate the remanent state and coercivity and select between hysteretic and non-hysteretic magneto-resistance states, even observing different magnetic scenarios when combining different number of layers – keeping the twist angle constant3. These results show that twisted CrSBr layers provide an ideal platform for studying and controlling field-induced phenomena in two-dimensions, offering new insights regarding 2D magnets and opening a fruitful playground for creating artificial magnetic symmetries and manipulating non-collinear magnetic textures their integration into vertical spintronic devices.
References:
1. 2. 3. Boix‐Constant, C. et al. Adv. Mater. 34, 1–8 (2022).
Boix-Constant, C. et al. Nat. Mater. 23, 212–218 (2024).
Boix‐Constant, C. et al. Adv. Mater. 37, 1–11 (2025).