Static and Dynamic Magnetic Properties of Cu-Based Organic-Inorganic Hybrid Perovskite Single Crystals

Low dimensional magnetism reported in Van der Waals (VdW) materials has sparked a renewed interest in spintronic applications in recent years, focusing on two dimensional spin waves and antiferromagnetic magnon generation. We investigate Cu-based hybrid organic-inorganic perovskites which represent an intriguing class of quasi two-dimensional layered materials, with far greater chemical (and magnetic) variability than their VdW counterparts, making them potentially suited for spintronic applications. Here we examine the static and dynamic magnetic properties of (C₆H₅CH₃CH₂NH₃)₂CuCl₄, (CH₃CH₂NH₃)₂CuCl₄, and (C₆H₅CH₃CH₂NH₃)₂CuBr₄ single crystals using SQUID magnetometry and ferromagnetic resonance (FMR) spectroscopy, respectively. Static magnetization and susceptibility measurements reveal the effects of organic cation and halide substitution on critical ordering behavior. Dynamic FMR measurements show spin-wave propagation in the paramagnetic region above the critical temperature as a result of strong intralayer exchange coupling. At the critical temperature, asymmetric FMR absorption occurs as interlayer exchange becomes relevant and additional spin-wave modes are manifested.