The discovery of the 1144-phase, e.g. CaKFe$_4$As$_4$, creates opportunities to build novel intermetallics with alternative stacking two parent compounds. Here we formalize idea by defining a class bulk crystalline solids $A$-$B$ (including 1144-phases and beyond), which is generalization hetero-structures from few-layer or thin-film semi-conductors intermetallics. Theoretically, four families ...
