Dynamic magnetic stripe communications devices may include a coil. An exchange coupled amorphous material may be inside the coil, for example, in the form of a ribbon. The exchange coupled amorphous material may include magnetically hard crystallites embedded in a soft magnetic amorphous matrix and/or at least one crystalline surface layer. A device may include a dynamic magnetic stripe communications device including one or more exchange coupled amorphous ribbons. The device may include more than one exchange coupled amorphous ribbon. Amorphous ribbons and/or layers of amorphous ribbons may be stacked (e.g., in alignment to one another) and/or offset at different heights. The ribbons may be in a single domain state without an external magnetic field, for example, an external magnetic field from a permanent magnet. The device may not include a permanent magnet.