Mesoscopic Theory of Resistive Switching

The quantum nature of filamentary-type resistive switching (RS) occurring in thin oxide films has been investigated for more than two decades and though the key concepts for a mesoscopic theory of RS are well known, establishing a simple phenomenological model consistent with the experimental observations has proven to be an elusive task. The physics of RS is complex because it involves the coupled action of electrons and ions or vacancies, a connection which gives rise to the hysteretic behavior of the conduction characteristic of the device. In this letter, a model based on the Landauer approach for the electron transport through a narrow constriction is revisited and combined with the master equation for the generation and dissolution of a nanosized gap. The proposed model not only sheds light on one of the most widely invoked equations for conduction in RS devices (Stanford-PKU RRAM model) but also provides the physical meaning of its parameters. The role played by the power dissipation at the two ends of the constriction during the occurrence of the switching process is also discussed.