  We propose spin transfer torque--magnetoresistive random access memory
(STT-MRAM) based on magneto-resistance and spin transfer torque physics of
band-pass spin filtering. Utilizing the electronic analogs of optical phenomena
such as anti-reflection coating and resonance for spintronic devices, we
present the design of an STT-MRAM device with improved features when compared
with a traditional trilayer device. The device consists of a superlattice
heterostructure terminated with the anti-reflective regions sandwiched between
the fixed and free ferromagnetic layers. Employing the Green's function spin
transport formalism coupled self-consistently with the stochastic
Landau-Lifshitz-Gilbert-Slonczewski equation, we present the design of an
STT-MRAM based on the band-pass filtering having an ultra-high TMR (3.5*10e4)
and large spin current. We demonstrate that the STT-MRAM design having
band-pass spin filtering are nearly 1100% more energy efficient than
traditional trilayer magnetic tunnel junction (MTJ) based STT-MRAM. We also
present detailed probabilistic switching and energy analysis for a trilayer MTJ
and band-pass filtering based STT-MRAM. Our predictions serve as a template to
consider the heterostructures for next-generation spintronic device
applications.
