Search

Your search keyword '"Quiñonez, Walter"' showing total 10 results
Start Over Author "Quiñonez, Walter"
10 results on '"Quiñonez, Walter"'

1. Effect of memristor\'s potentiation-depression curves peculiarities in the convergence of physical perceptrons

Author

Quiñonez, Walter, Sánchez, María José, and Rubi, Diego

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Computer Science - Emerging Technologies
Abstract

Neuromorphic computing aims to emulate the architecture and information processing mechanisms of the mammalian brain. This includes the implementation by hardware of neural networks. Oxide-based memristor arrays with cross-bar architecture appear as a possible physical implementation of neural networks.In this paper, we obtain experimental potentiation-depression (P-D) curves on different manganite-based memristive systems and simulate the learning process of perceptrons for character recognition. We analyze how the specific characteristics of the P-D curves affect the convergence time -- characterized by the EPOCHs-to-convergence (ETC) parameter -- of the network. Our work shows that ETC is reduced for systems displaying P-D curves with relatively low granularity and non-linear and asymmetric response. In addition, we also show that noise injection during the synaptic weight actualization further reduces the ETC. The results obtained here are expected to contribute to the optimization of hardware neural networks based on memristors cross-bar arrays., Comment: 10 pages published version

Published
2023
Full Text
View/download PDF

2. Oxygen vacancy dynamics in Pt/TiOx/TaOy/Pt memristors: exchange with the environment and internal electromigration

Author

Martir, Rodrigo Leal, Sánchez, María José, Aguirre, Myriam, Quiñonez, Walter, Ferreyra, Cristian, Acha, Carlos, Lecourt, Jerome, Lüders, Ulrike, and Rubi, Diego

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

Memristors are expected to be one of the key building blocks for the development of new bio-inspired nanoelectronics. Memristive effects in transition metal oxides are usually linked to the electromigration at the nanoscale of charged oxygen vacancies (OV). In this paper we address, for Pt/TiOx/TaOy/Pt devices, the exchange of OV between the device and the environment upon the application of electrical stress. From a combination of experiments and theoretical simulations we determine that both TiOx and TaOy layers oxidize, via environmental oxygen uptake, during the electroforming process. Once the memristive effect is stabilized (post-forming behavior) our results suggest that oxygen exchange with the environment is suppressed and the OV dynamics that drives the memristive behavior is restricted to an internal electromigration between TiOx and TaOy layers. Our work provides relevant information for the design of reliable binary oxide memristive devices., Comment: preprint 20 pages, 4 figures

Published
2022
Full Text
View/download PDF

4. Oxygen vacancy dynamics in Pt/TiOx/TaOy/Pt memristors: exchange with the environment and internal electromigration

Author

Universidad Nacional de Cuyo, Agencia Nacional de Promoción Científica y Tecnológica (Argentina), European Commission, Leal Martir, Rodrigo, Sánchez, M. J., Aguirre, Myriam H., Quiñonez, Walter, Ferreyra, C., Acha, C., Lecourt, J., Lüders, Ulrike, Rubi, Diego, Universidad Nacional de Cuyo, Agencia Nacional de Promoción Científica y Tecnológica (Argentina), European Commission, Leal Martir, Rodrigo, Sánchez, M. J., Aguirre, Myriam H., Quiñonez, Walter, Ferreyra, C., Acha, C., Lecourt, J., Lüders, Ulrike, and Rubi, Diego

Abstract

Memristors are expected to be one of the key building blocks for the development of new bio-inspired nanoelectronics. Memristive effects in transition metal oxides are usually linked to the electromigration at the nanoscale of charged oxygen vacancies (OV). In this paper we address, for Pt/TiOx/TaOy/Pt devices, the exchange of OV between the device and the environment upon the application of electrical stress. From a combination of experiments and theoretical simulations we determine that both TiOx and TaOy layers oxidize, via environmental oxygen uptake, during the electroforming process. Once the memristive effect is stabilized (post-forming behavior) our results suggest that oxygen exchange with the environment is suppressed and the OV dynamics that drives the memristive behavior is restricted to an internal electromigration between TiOx and TaOy layers. Our work provides relevant information for the design of reliable binary oxide memristive devices.

Published
2023

7. Oxygen vacancy dynamics in Pt/TiOx/TaOy/Pt memristors: exchange with the environment and internal electromigration.

Author

Leal Martir, Rodrigo, José Sánchez, María, Aguirre, Myriam, Quiñonez, Walter, Ferreyra, Cristian, Acha, Carlos, Lecourt, Jerome, Lüders, Ulrike, and Rubi, Diego

Subjects
ELECTRODIFFUSION, MEMRISTORS, OXYGEN, INFORMATION design, TRANSITION metal oxides, OXYGEN reduction
Abstract

Memristors are expected to be one of the key building blocks for the development of new bio-inspired nanoelectronics. Memristive effects in transition metal oxides are usually linked to the electromigration at the nanoscale of charged oxygen vacancies (OV). In this paper we address, for Pt/TiO x /TaO y /Pt devices, the exchange of OV between the device and the environment upon the application of electrical stress. From a combination of experiments and theoretical simulations we determine that both TiO x and TaO y layers oxidize, via environmental oxygen uptake, during the electroforming process. Once the memristive effect is stabilized (post-forming behavior) our results suggest that oxygen exchange with the environment is suppressed and the OV dynamics that drives the memristive behavior is restricted to an internal electromigration between TiO x and TaO y layers. Our work provides relevant information for the design of reliable binary oxide memristive devices. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

9. Reflexiones sobre la universidad y la sociedad

Author

Castillo Cabeza, Segundo N., Canchingre Bone, Luis A., Becerra Quiñonez, Walter V., Castillo Cabeza, Segundo N., Canchingre Bone, Luis A., and Becerra Quiñonez, Walter V.

Abstract

Las universidades forman parte de las instituciones sociales, que juegan un papel fundamental en la transformación de las sociedades. A través de estas instituciones que transmiten a los individuos el conocimiento intelectual indispensable para la modernización y la democratización de la sociedad. A tales efectos se detallan algunos aspectos de interés, tales como: la universidad, como institución social, su actualidad, su papel, su situación en el mundo cambiante y globalizado, Situación actual en Ecuador. Podemos concluir que las universidades atiende la formación humanista y profesional del hombre, en la que nos lleva a pensar que estas tareas deben ampliarse a la sociedad; es decir, no se pretende formar al hombre como individuo aislado sino como persona, parte esencial de la sociedad. En consecuencia cuando hablamos de la formación profesional nos referimos tanto al desarrollo de habilidades y capacidades del individuo que lo harán un hombre íntegro, pero también al impacto que dichas habilidades tengan en la vida social.

Published
2016

10. Oxygen vacancy dynamics in Pt/TiO x /TaO y /Pt memristors: exchange with the environment and internal electromigration.

Author

Leal Martir R, José Sánchez M, Aguirre M, Quiñonez W, Ferreyra C, Acha C, Lecourt J, Lüders U, and Rubi D

Abstract

Memristors are expected to be one of the key building blocks for the development of new bio-inspired nanoelectronics. Memristive effects in transition metal oxides are usually linked to the electromigration at the nanoscale of charged oxygen vacancies (OV). In this paper we address, for Pt/TiO x /TaO y /Pt devices, the exchange of OV between the device and the environment upon the application of electrical stress. From a combination of experiments and theoretical simulations we determine that both TiO x and TaO y layers oxidize, via environmental oxygen uptake, during the electroforming process. Once the memristive effect is stabilized (post-forming behavior) our results suggest that oxygen exchange with the environment is suppressed and the OV dynamics that drives the memristive behavior is restricted to an internal electromigration between TiO x and TaO y layers. Our work provides relevant information for the design of reliable binary oxide memristive devices., (© 2022 IOP Publishing Ltd.)

Published
2022
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results