Michael Thomas

In this study, MuMax3 magnetic simulations were used to determine the switching window of ferromagnet-InSb nanowire spin-transistor devices with varying geometries. The goal of the study was to optimize these devices in simulations in preparation for nanofabrication of the most promising designs for further testing. Spin-transistor devices are improvements on the common charge-based transistor that use the magnetic spin of electrons on either side of the device. These devices are still in development but should be able to use less energy than current transistors. Working spin-transistors could also be used for solid state data storage. In order for a spin-transistor device to be successful, it is important that the two magnetic leads of the device switch magnetic polarization cleanly and that there is a window between the magnetic field needed to switch the first lead and the second. Because of this, simulations were designed to find the optimal geometry for wide, clean switching windows. Widths of ferromagnets from 150 nm to 1 µm were simulated, and wider ferromagnets were shown to switch at lower external magnetic fields, but with less clean switching. Because of this balance between a large window and a clean switch, it was found that the best pair of magnetic lead widths is 150 nm and 300 nm. Clean switches were also demonstrated for gaps between the ferromagnets up to 1 µm.