Energy efficient straintronic computing: Boolean and non-Boolean
information processing with strain-mediated switching of
nanomagnets with electric fields
Jayasimha Atulasimha
Virginia Commonwealth University
This talk will start with a brief introduction on magnetostrictive materials. Thereafter, our current
research in the newly emerging area of multiferroic nanomagnet based ultra low power
computing will be discussed. Specifically, our groups have shown that multiferroic nanomagnets
(consisting of a piezoelectric and a magnetostrictive layer) can be used to perform computing
while dissipating 3 orders of magnitude less energy than current transistors at clock rates of
~1GHz acting as memory elements, logic wires, gates and associative memory for higher order
computing such as ultrafast image reconstruction and pattern recognition.
We have recently implemented strain clocked nanomagnetic logic and information propagation
in a nanomagnetic array experimentally using elliptical magnetostrictive nanomagnets of
nominal lateral dimensions ~ 100 nm and thickness ~10 nm that have been fabricated by ebeam lithography on piezoelectric substrates. Simulations to model the switching error in such
dipole coupled nanomagnetic systems and new schemes to mitigate such errors will also be
presented. Finally, magnetic tunnel junction based multiferroic nanomagnetic architectures that
could lead to practical ultra-low-power memory, digital and analog computing paradigms will be
discussed. A straintronic-spin neuron proposal that combines the threshold switching behavior
of nanomagnets with energy efficiency of strain based magnetic switching will also be
presented.
Finally, we also discuss another intriguing proposal that combine the areas of sensing and
computing: studying ferromagnet/semiconductor/ferromagnet nanowire heterostructures where
stress induced rotation of magnetization of the ferromagnetic layer can change the spin-filtering
efficiency and be used for ultrasensitive strain detection. In this regard, we show recent results
on coherent spin transport at room temperature in ~100 nm long InSb nanowires with single
subband occupancy due to suppression of spin relaxation.
This work is support by NSF under the NEB2020 grant ECCS-1124714, CAREER grant CCF1253370, SHF Grant CCF-1216614 and CMMI grant CMMI-1301013 as well as the
Semiconductor Research Corporation under NRI task 2203.001.