Overview

The Center for NanoFerroic Devices (CNFD) is led by the University of Nebraska-Lincoln (UNL), and partners with researchers from University of California at Irvine (UCI), University of Wisconsin-Madison (UWM), University at Buffalo, SUNY (UB), University of Delaware (UD), and Oakland University (OU). CNFD’s mission is to develop non-conventional, low-energy devices based on innovative functional materials systems and conceptually novel approaches for device operation. Research involves exploration of properties, materials, structures, and phenomena non-traditional for existing technologies, such as magnetoelectricity, ferroelectricity, and spin dynamics. CNFD exploits these concepts in novel devices utilizing state variables different from charge and exhibiting significant switching effects that are robust enough to be harnessed as manufacturable technologies.

Research Focus

CNFD research is organized within three themes:

Magnetoelectric Devices – This theme is focused on nonvolatile magnetoelectric (ME) devices that utilize voltage-controlled boundary magnetization in magnetoelectric antiferromagnets. The goal is to develop a spintronic device based on a magnetic tunnel junction (MTJ), where the magnetization of a free magnetic layer is voltage controlled through exchange interaction with the boundary magnetization of the adjacent magnetoelectric layer (ME-MTJ). This theme also develops a novel logic device – spinverter – that exploits nonvolatility of the ME-MTJ in the basic CMOS element.

Ferroelectric Devices – This theme is centered on devices that exploit ferroelectric polarization as a state variable and reveal polarization controlled electron and spin tunneling and metal-insulator transitions. The goal is to develop a ferroelectric tunnel junction (FTJ) exhibiting switchable tunneling resistance with resistance ratios exceeding 103 at room temperature. This theme also develops a ferroelectric field effect transistor (FET) with a programmable Schottky barrier, based on polarization induced metal-insulator transition in correlated oxide materials.

Spin Wave Devices – This Theme is focused on logic devices involving propagation of spin waves in ferromagnetic nanowires where the state variable is either the phase or the frequency of the propagating spin wave. The goal is to develop a majority logic gate (MLG) based on interference of spin wave signals using energy-efficient methods for excitation and manipulation of spin waves through voltage-controlled magnetic anisotropy. This theme also develops a spin wave field effect transistor (SW-FET) enabling spin wave manipulation using the voltage control of the spin wave dispersion relation.