Asymmetric pulsing for reliable operation of titanium/manganite memristors

Abstract

We present a pulsing protocol that significantly increases the endurance of a titanium-manganite interface used as a binary memory cell. The core of this protocol is an algorithm that searches for the proper values for the set and reset pulses, canceling the drift in the resistance values. A set of experiments show the drift-free operation for more than 10 5 switching cycles, as well as the detrimental effect by changing the amplitude of pulses indicated by the protocol. We reproduced the results with a numerical model, which provides information on the dynamics of the oxygen vacancies during the switching cycles.

Numerical and experimental study of stochastic resistive switching

“…The behavior of this material has already been studied in, e.g., Refs. [21,22,29,30]. The experimental setup is shown in Fig.…”

“…There are different mechanisms proposed to explain the observed behavior of resistive switching materials (see, e.g., Refs. [14,15,[18][19][20][21][22] and references therein). From a macroscopic point of view, one of the simplest models is that proposed in Ref.…”

Optimization of resistive switching performance of metal-manganite oxide interfaces by a multipulse protocol

“…[6][7][8][9] Strategies based on cancelling the drift using an asymmetric amplitude pulsing protocol were also shown to be successful. 10 Following these ideas here, we propose as a possible strategy to optimize the performance of the device, a multipulse protocol that consist of applying pulses of a single polarity to a given HR state. We show, both through experiments and modelling, that in this case, the resistance evolves to (much) higher values than the initial HR state, increasing the HR/LR ratio, and thus the performance of the device as a memory cell.…”

Thermal effects on the switching kinetics of silver/manganite memristive systems

“…As stated in that work, the defects distribution is strongly related to the RS properties, assisting the Ov migration and making more efficient the ReRAM operation.Although the exact microscopic origin behind the RS effect remains elusive, a recent phenomenological model, named voltage enhanced oxygen vacancy (VEOV) migration model, [21] succeeded in reproducing many non trivial characteristic of bipolar RS experiments carried in complex oxides, under different stimulus protocols. [12,13,22] The VEOV model incorporates as main ingredients (i) the drift/diffusion of Ov along the highly resistive metal/oxide interfaces, where strong electric fields developed and (ii) a linear relation between resistivity and Ov concentration. Thus, according to the model, the local change in the concentration of Ov near the electrodes modifies the contact resistance, as follows from (ii).…”

“…The negative polarity of the reset pulse forces Ov to move from the bulk to the interface region, increasing its resistance R A . [12] However, the Ov distribution is far from equilibrium; the reset pulse does not succeed in introducing vacancies homogeneously in all the interface and some nanoscale regions remain void of vacancies. After the reset pulse, the dynamics is governed by diffusion.…”