Spin-polarized charge fluctuations in magnetic tunneling diodes

We have studied the spin-dependent transport properties in CdTe/Cd1−xMnxTe resonant tunneling diodes. Our results show that spin polarized shot-noise currents can be enhanced if compared to the unpolarized ones. For the geometry of samples studied, only a partial shot-noise suppression was observed near the end of the negative differential resistance region. Just above the threshold of tunneling to a given resonant Landau level the noise reaches a maximum. The details on the population of these levels at given voltage can help design efficient low voltage (V<10 mV) spin-filter devices using small barrier offset (V0∼10 meV) and magnetic field (B0⩽5 T).