Proposal for a ferromagnetic multiwell spin oscillator

The highly nonlinear coupling of transport and magnetic properties in a multiwell heterostructure, which comprises ferromagnetic quantum wells made of diluted magnetic semiconductors, is theoretically investigated. The interplay of resonant tunneling and carrier-mediated ferromagnetism in the magnetic wells induces very robust, self-sustained current and magnetization oscillations. Over a large window of steady bias voltages the spin polarization of the collector current is oscillating between positive and negative values, realizing a spin oscillator device.