Manipulation and readout of spin states of a single-molecule magnet by a spin-polarized current

Single-molecule memory device based on a single-molecule magnet (SMM) is one of the ultimate goals semiconductor nanofabrication technologies. Here, we study how to manipulate and readout SMM's two spin-state stored information that characterized by maximum minimum average value $Z$-component total spin SMM conduction-electron, which are recognized as bits "$1$" "$0$". We demonstrate switching time depends both sequential tunneling gap $\varepsilon_{se}$ spin-selection-rule allowed transition-energy $\varepsilon_{trans}$, can be tuned gate voltage. In particular, when external bias voltage turned off, in cases unoccupied doubly-occupied ground eigenstates, derivative transport current used read out information. Moreover, strength asymmetry SMM-electrode coupling have strong influence time, but slight being order nanoseconds. Our results suggest SMM-based device, provide fundamental insight into electrical controllable manipulation