Oxygen vacancies for memristive response
Artificial Intelligence aims to develop computer systems capable of performing tasks complex skills such as voice and pattern recognition or decision-making, mimicking capabilities of the human brain. At present, new materials and devices are intensively researched able to perform these tasks efficiently. In a joint work of researchers of the MELON, from CNEA-CONICET and RUG, published in Phys. Rev. Appl. 44 , 044045 (2020) it was found that both non-volatile and volatile electrical resistance changes, which can replicate the behavior of brain synapses and neurons, respectively, coexist in ferroelectric capacitors. From experiments and phenomenological modeling, it was evidenced that the physical origin of the resistance changes is based on the combination of an electronic effect, linked to the reversal of ferroelectric polarization, and the electromigration of oxygen vacancies, both modulating the energy barriers present at the interfaces between the ferroelectric layer and the metal electrodes. It was shown that both mechanisms are strongly intertwined and that the observed resistance relaxations are associated with electromigration of oxygen vacancies, dominated by the depolarizing electric field usually present in ferroelectric thin films. The results reported in this work will contribute to the development of neuromorphic computing devices. (Adopted from Gacetilla INN Octubre 2020)
Invited talk by D. Rubi at 2020 Annual Meeting of Institute of Nanoscience and Nanotechnology (INN-CNEA-CONICET BA & Bariloche). In Spanish. Open ...