Magneto-excitonic duality from monolayer to trilayer CrSBr

This work investigates the magneto-excitonic properties of mono-, bi-, and trilayer CrSBr using photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopy. The results reveal a dual excitonic behaviour where Frenkel-like and Wannier–Mott-like excitons coexist in the same layered magnetic material. Layer-dependent optical measurements show distinct responses for monolayer, bilayer, and trilayer structures. Magnetic-field-dependent spectroscopy demonstrates strong excitonic shifts and highlights the coupling between magnetic ordering and excitonic states in CrSBr. The findings provide insight into hybrid excitonic behaviour in layered magnetic materials and open new opportunities for magneto-optoelectronic applications.