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10 MeV proton-irradiation effects on a YBCO-based test structure were analyzed by measuring its current-voltage (IV) characteristics for different cumulated fluences. For fluences of up to $\sim$80$\cdot$10$^9$~p/cm$^2$ no changes in the electrical behavior of the device were observed, while for a fluence of $\sim$~300$\cdot$10$^9~$ p/cm$^2$ it becomes less conducting. A detailed analysis of the room temperature IV characteristics based on the $\gamma$ power exponent parameter [$\gamma=dLn(I)/dLn(V)$] allowed us to reveal the main conduction mechanisms as well as to establish the equivalent circuit model of the device. The changes produced in the electrical behavior, in accordance with Monte Carlo TRIM simulations, suggest that the main effect induced by protons is the displacement of oxygen atoms within the YBCO lattice, particularly from oxygen-rich to oxygen-poor areas, where they become trapped., Comment: 22 pages, 7 figures, corresponding author: acha@df.uba.ar

LabOSat (acronym for “Laboratory On a Satellite”) is a type of electronic platform designed to perform experiments in harsh, remote environments. Up to now, LabOSat platforms have been used mainly for characterizing and validating custom and commercial electronic devices at Low Earth Orbits (LEO). Many of these platforms are running experiments aboard ÑuSat satellites, which are built and operated by Argentine company Satellogic. A brief description of LabOSat platforms is presented here, along with details of their validation both at LEO and at a nuclear reactor. The electrical characterization of custom non-volatile memory cells — as performed by a LabOSat platform at LEO — is also described, and the results of such experiment are compared with results obtained on Earth. The memory cells studied were TiO2-based and La1/3Ca2/3MnO3-based ReRAM devices. Fil: Barella, Mariano. Instituto Nacional de Tecnología Industrial. Centro de Micro y Nanoelectrónica del Bicentenario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sanca, Gabriel Andrés. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina Fil: Gomez Marlasca, Fernando. Comisión Nacional de Energía Atómica; Argentina Fil: Acevedo, W. Román. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rubi, Diego. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: García Inza, Mariano Andrés. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Física de Dispositivos Microelectrónica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Levy, Pablo Eduardo. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Golmar, Federico. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Industrial. Centro de Micro y Nanoelectrónica del Bicentenario; Argentina International Forum on Advances in Radiation Physics Buenos Aires Argentina Università di Bologna

In this work the characteristics and performance of LabOSat platform to carry out experiments over electronic devices in aggressive environments are described. Configurable, portable, low weight and low cost are the main features. First measurements made in our laboratory are presented before testing in space.

We report on non-volatile memory devices based on multifunctional manganites. The electric field induced resistive switching of Ti/$La_{1/3}$$Ca_{2/3}$Mn$O_3$/n-Si devices is explored using different measurement protocols. We show that using current as the electrical stimulus (instead of standard voltage-controlled protocols) improves the electrical performance of our devices and unveils an intermediate resistance state. We observe three discrete resistance levels (low, intermediate and high), which can be set either by the application of current-voltage ramps or by means of single pulses. These states exhibit retention and endurance capabilities exceeding $10^4$ s and 70 cycles, respectively. We rationalize our experimental observations by proposing a mixed scenario were a metallic filament and a Si$O_x$ layer coexist, accounting for the observed resistive switching. Overall electrode area dependence and temperature dependent resistance measurements support our scenario. After device failure takes place, the system can be turned functional again by heating up to low temperature (120 C), a feature that could be exploited for the design of memristive devices with self-healing functionality. These results give insight into the existence of multiple resistive switching mechanisms in manganite-based memristive systems and provide strategies for controlling them., 17 pages, 7 figures, to appear in Phys. Lett. A

We report resistive switching effects in polycrystalline samples of the multiferroic Bi 0.9 Ca 0.1 FeO 3 with silver electrodes. Mossbauer spectroscopy shows that upon Ca-doping the Fe remains in a 3+ valence state, suggesting charge compensation through the creation of large amounts of oxygen vacancies. Electrical characterization shows that the oxide/metal resistance can be switched between high and low resistance states by applying voltage pulses. This process was shown to be forming free and a strong relaxation after switching was found. We rationalize our results by considering oxygen vacancies migration to and from the metal–oxide interface, resulting in variations of the Schottky potential barrier height that modulate the interface resistance.

International audience

We studied La0.325Pr0.300Ca0.375MnO3-Ag memristive interfaces. We present a pulsing/measuring protocol capable of registering both quasi-static i-v data and non-volatile remnant resistance. This protocol allowed distinguishing two different electronic transport mechanisms coexisting at the memristive interface, namely space charge limited current and thermionic emission limited current. We introduce a 2-element electric model that accounts for the obtained results and allows predicting the quasi-static i-v relation of the interface by means of a simple function of both the applied voltage and the remnant resistance value. Each element of the electric model is associated to one of the electronic transport mechanisms found. This electric model could result useful for developing time-domain simulation models of metal-manganite memristive interfaces. Fil: Gomez Marlasca, F.. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina Fil: Ghenzi, Néstor. Comisión Nacional de Energía Atómica; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Leyva, Adelma Graciela. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina Fil: Albornoz, Cecilia Andrea. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina Fil: Stoliar, Pablo Alberto. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina Fil: Rubi, Diego. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Levy, Pablo Eduardo. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

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., 10 pages, 4 figures. To be published in Applied Physics Letters

We report a heat dynamics analysis of the electrocaloric effect (ECE) in commercial multilayer capacitors based on BaTiO3 dielectric, a promising candidate for applications as a solid state cooling device. Direct measurements of the time evolution of the sample's temperature changes under different applied voltages allow us to decouple the contributions from Joule heating and from the ECE. Heat balance equations were used to model the thermal coupling between different parts of the system. Fingerprints of Joule heating and the ECE could be resolved at different time scales. We argue that Joule heating and the thermal coupling of the device to the environment must be carefully taken in to account in future developments of refrigeration technologies employing the ECE., Comment: Acepted to be published in Applied Phys. Letters (2011)

We introduce a model that accounts for the bipolar resistive switching phenomenom observed in transition metal oxides. It qualitatively describes the electric field-enhanced migration of oxygen vacancies at the nano-scale. The numerical study of the model predicts that strong electric fields develop in the highly resistive dielectric-electrode interfaces, leading to a spatially inhomogeneous oxygen vacancies distribution and a concomitant resistive switching effect. The theoretical results qualitatively reproduce non-trivial resistance hysteresis experiments that we also report, providing key validation to our model., Accepted for publication in Physical Review B, 6 twocolumn pages, 5 figures

Multilevel resistance states in silver-manganite interfaces are studied both experimentally and through a realistic model that includes as a main ingredient the oxygen vacancies diffusion under applied electric fields. The switching threshold and amplitude studied through Hysteresis Switching Loops are found to depend critically on the initial state. The associated vacancy profiles further unveil the prominent role of the effective electric field acting at the interfaces. While experimental results validate main assumptions of the model, the simulations allow to disentangle the microscopic mechanisms behind the resistive switching in metal-transition metal oxide interfaces., Comment: 14 pages, 3 figures, to be published in Jour. of Appl. Phys

Bipolar resistive switching in low cost n-Si/La2/3Ca1/3MnO3/M (M¼TiþCu) devices was investigated. For low SET compliance currents (CC), an interfacial-related resistive switching mechanism, associated to the migration of oxygen vacancies close to the manganite/metal interface, is operative. Simulations using the voltage enhanced oxygen vacancies drift model validate our experimental results. When further increasing the CC, we have observed the onset of a second, filamentary, resistive switching regime with a concomitant collapse of the ON/OFF ratio. We finally demonstrate that it is possible to delay the onset of the filamentary regime by controlling the film thickness. Fil: Rubi, Diego. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Tesler, Federico Ariel. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Alposta, I.. Comisión Nacional de Energía Atómica; Argentina Fil: Kalstein, Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; Argentina Fil: Ghenzi, Néstor. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Gomez Marlasca, F.. Comisión Nacional de Energía Atómica; Argentina Fil: Rozenberg, Marcelo Javier. Universite Paris Sud; Francia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Levy, Pablo Eduardo. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

We study electroforming on the resistive switching (RS) behavior of silver-manganite interfaces. Using the technique of hysteresis switching loops we define an electroforming procedure that enables us to study its influence on the RS behavior in a systematic manner. We show that two similar electroforming procedures may lead to either RS or no RS at all. We explain the observed behavior by associating the forming procedure and the memory switching operation to major and minor hysteresis loops, respectively. With the obtained insight we propose a simple and nearly optimal electroforming procedure.

We investigate the electric pulse induced resistance switching in a transition metal oxide-metal contact at room temperature ? a non volatile, reversible and multilevel memory device. Using a simple multiterminal configuration, we find that the complementary effect -in which the contact resistance of each pulsed electrode displays variations of opposite sign- is strongly influenced by the history of the pulsing procedure. Loops performed by varying the magnitude and sign of the stimulus at each pulsed electrode allow to disentangle their sole contribution at different stages of the process. Electromigration of oxygen ions and vacancies is discussed as participating at the core of the underlying mechanisms for resistance switching.