arXiv subjects

Jayasimha Atulasimha

Publications and source records attributed to Jayasimha Atulasimha.

75 records · Page 5Linked to original sources

arXiv2011

Hybrid spintronics and straintronics: A magnetic technology for ultra low energy computing and signal processing

The authors show that the magnetization of a magnetostrictive/piezoelectric multiferroic single-domain shape-anisotropic nanomagnet can be switched with very small voltages that generate strain in the magnetostrictive layer. This can be the basis of ultralow power computing and signal processing. With appropriate material choice, the energy dissipated per switching event can be reduced to $\sim$45 $kT$ at room temperature for a switching delay of $\sim$100 ns and $\sim$70 $kT$ for a switching delay of $\sim$10 ns, if the energy barrier separating the two stable magnetization directions is $\sim$32 $kT$. Such devices can be powered by harvesting energy exclusively from the environment without the need for a battery.

cond-mat.mes-hall↗

arXiv2011

Four-state nanomagnetic logic using multiferroics

The authors show how to implement a 4-state universal logic gate (NOR) using three strain-coupled magnetostrictive-piezoelectric multiferroic nanomagnets (e.g. Ni/PZT) with biaxial magnetocrystalline anisotropy. Two of the nanomagnets encode the 2-state input bits in their magnetization orientations and the third nanomagnet produces the output bit via dipole interaction with the input nanomagnets. A voltage pulse alternating between -0.2 V and +0.2 V is applied to the PZT layer of the third nanomagnet and generates alternating tensile and compressive stress in its Ni layer to produce the output bit, while dissipating ~ 57,000 kT (0.24 fJ) of energy per gate operation.

cond-mat.mes-hall↗

arXiv2010

Energy-efficient mixed mode switching of a multiferroic nanomagnet for logic and memory

In magnetic memory and logic devices, a magnet's magnetization is usually flipped with a spin polarized current delivering a spin transfer torque (STT). This mode of switching consumes too much energy and considerable energy saving can accrue from using a multiferroic nanomagnet switched with a combination of STT and mechanical stress generated with a voltage (VGS). The VGS mode consumes less energy than STT, but cannot rotate magnetization by more than 90?, so that a combination of the two modes is needed for energy-efficient switching.

cond-mat.mes-hall↗