Features of the Resistive Switching of Memristors Based on a (CoFeB)x(LiNbO3)100–x Nanocomposite with a Ni Electrode: Influence of Temperature and Magnetic Field

Abstract

The properties of Cu/NC/D/Ni memristive structures with a (CoFeB)_x(LiNbO₃)_100–x nanocomposite layer and a LiNbO₃ dielectric layer with a thicknesses of 230 and 20 nm, respectively, are studied. It is found that the resistive switching (RS) voltage of the structures decreases greatly from 2.4 to 0.5 V with increasing temperature from 270 to 380 K. The negative magnetoresistance (MR) and its noticeable influence on the voltage and current of RS, which reaches ~5% with a MR value of 1.8%, is revealed. The peculiarity of the RS structure effect is associated with the fairly efficient injection of spin-polarized electrons from the Ni electrode into the conduction band of the LiNbO₃ layer at positive bias voltages of the upper Cu electrode. In this case, the filling of deep energy-distributed traps in the LiNbO₃ layer, which is observed above a certain voltage applied to the structure, leads to a sharp increase in current and manifestation of the RS effect, depending on both temperature and magnetic field. Under these conditions the structures demonstrate spike-timing-dependent plasticity (STDP), which confirms the possibility of their use as synapses in the development of neuromorphic systems.