  The exploration of two-dimensional (2D) antiferromagnetic (AFM) materials has
shown great promise and interest in tuning the magnetic and electronic
properties as well as studying magneto-optical effects. The current work
investigates the control of magneto-optical interactions in alloyed MnxZn1-xPS3
lamellar semiconductor single crystals, with the Mn/Zn ratio regulating the
coupling strength. Magnetic susceptibility results show a retention of AFM
order followed by a decrease in N\'eel temperatures down to ~ 40% Mn
concentration, below which a paramagnetic behavior is observed. Absorption
measurements reveal an increase in bandgap energy with higher Zn(II)
concentration, and the presence of Mn(II) d-d transition below the absorption
edge. DFT+U approach qualitatively explained the origin and the position of the
experimentally observed mid band-gap states in pure MnPS3, and corresponding
peaks visible in the alloyed systems MnxZn1-xPS3. Accordingly, emission at 1.3
eV in all alloyed compounds results from recombination from a 4T1g Mn(II)
excited state to a hybrid p-d state at the valence band. Most significant,
temperature-dependent photoluminescence (PL) intensity trends demonstrate
strong magneto-optical coupling in compositions with x > 0.65. This study
underscores the potential of tailored alloy compositions as a means to control
magnetic and optical properties in 2D materials, paving the way for advances in
spin-based technologies.
