Impact of Number of Paramagnetic Nanostructure Coupled With Two Ferromagnetic Electrodes of a Cross-Junction-Shaped Molecular Spintronics Device at Different Thermal Energies

Nanoscale molecular spintronics devices (MSDs) are poised to transform logic and memory technologies. Paramagnetic nanostructures, such as molecules exchange-coupled to ferromagnetic electrodes, can yield novel magnetic material properties. Break-junction nanogap-based MSDs enable single-molecule devices, while magnetic tunnel junctions (MTJs) with sub-2 nm gaps allow for thousands of spin channels, potentially transforming MTJs. However, the role of varying numbers of paramagnetic nanostructures within the device and its stability over time and temperature remains unexplored. This study uses an MTJ-based MSD (MTJMSD) architecture with a Heisenberg model to simulate the magnetic effects of molecular nanostructures along the MTJ perimeter. By varying molecular populations, we analyze the MTJMSD’s magnetic moment and spatial correlations under different thermal energies. The findings reveal atomistic spatio temporal insights into the impact of molecular population and thermal factors on MTJMSD and its components, two ferromagnetic electrodes, and molecular analog.