Strain dependent properties of FeTe_xSe_1-x surfaces and monolayers

We performed computational studies of FeTe_xSe_1-x, an iron based superconductor. FeTe_xSe_1-x is also known to have topological properties, and is a candidate material for finding marjorana fermions. We used ab initio density functional theory simulations to calculate bandstructure and magnetization information for bulk, surface, and monolayer FeTe_xSe_1-x for several values of x. We study strain dependent properties and find several tunable properties of note, including flat bands, band splitting, and Dirac cones. We predict how strain dependence could be used to tune layers of FeTe_xSe_1-x for desired properties.