A5018927394- Advanced Memory and Neural Computing
- Electronic and Structural Properties of Oxides
- Magnetic and transport properties of perovskites and related materials
- Semiconductor materials and devices
- Magnetic properties of thin films
- Ferroelectric and Negative Capacitance Devices
- ZnO doping and properties
- Spacecraft Design and Technology
- Radiation Detection and Scintillator Technologies
- Molecular Junctions and Nanostructures
- Plasmonic and Surface Plasmon Research
- Radiation Effects in Electronics
- Magnetic Properties and Synthesis of Ferrites
- Neuroscience and Neural Engineering
- CCD and CMOS Imaging Sensors
- Quantum and electron transport phenomena
- Near-Field Optical Microscopy
- Organic Electronics and Photovoltaics
- Physics of Superconductivity and Magnetism
- Ferroelectric and Piezoelectric Materials
- Photonic and Optical Devices
- Theoretical and Computational Physics
- Surface and Thin Film Phenomena
- Copper-based nanomaterials and applications
- Multiferroics and related materials
National University of General San Martín
2014-2024
Consejo Nacional de Investigaciones Científicas y Técnicas
2013-2024
National Institute of Industrial Technology
2015-2023
Centro Científico Tecnológico - San Juan
2015-2019
CIC nanoGUNE
2011-2016
Universidad Nacional de San Martín
2015
University of Buenos Aires
2005-2010
Graphene plasmons promise unique possibilities for controlling light in nanoscale devices and merging optics with electronics. We developed a versatile platform technology based on resonant optical antennas conductivity patterns launching control of propagating graphene plasmons, an essential step the development plasmonic circuits. launched focused infrared geometrically tailored observed how they refracted when passing through two-dimensional pattern, here prism-shaped bilayer. To that...
Light scattering at nanoparticles and molecules can be dramatically enhanced in the 'hot spots' of optical antennas, where incident light is highly concentrated. Although this effect widely applied surface-enhanced sensing, spectroscopy microscopy, underlying electromagnetic mechanism signal enhancement challenging to trace experimentally. Here we study elastically scattered from an individual object located well-defined hot spot single as a new approach resolve role antenna process. We...
In recent years there has been an intense search for room temperature ferromagnetism in doped dilute semiconductors, which have many potentially applications spintronics and optoelectronics. We report here the unexpected observation of significant a semiconductor with nonmagnetic impurities, Cu-doped TiO$_2$ thin films grown by Pulsed Laser Deposition. The magnetic moment, calculated from magnetization curves, resulted surprisingly large, about 1.5 $\mu_B$ per Cu atom. A large moment was...
Theory predicts a distinct spectral shift between the near- and far-field optical response of plasmonic antennas. Here we combine near-field microscopy spectroscopy individual infrared-resonant nanoantennas to verify experimentally this shift. Numerical calculations corroborate our experimental results. We furthermore discuss implications effect in surface-enhanced infrared spectroscopy.
Carbon-based spin valves, composed of a C60 layer sandwiched between two magnetic materials show room temperature transport for fullerene thickness up to 30 nm. This result, interpreted by multistep tunnelling model, represents an advance in the field carbon spintronics.
Sketch of the configuration a light-controlled resistive switching memory. Light enters through Al2O3 uncovered surface and reaches optically active p-Si substrate, where carriers are photogenerated subsequently injected in layer when suitable voltage pulse is applied. The resistance can be switched between different non-volatile states, depending on applied illumination conditions.
An unprecedented control of the spectral response plasmonic nanoantennas has recently been achieved by designing structures that exhibit Fano resonances. This new insight is paving way for a variety applications, such as biochemical sensing and surface-enhanced Raman spectroscopy. Here we use scattering-type near-field optical microscopy to map spatial field distribution modes in infrared systems. We observe real space interference narrow (dark) broad (bright) resonances, yielding intensity...
The increasing complexity of composite materials structured on the nanometer scale requires highly sensitive analytical tools for nanoscale chemical identification, ideally in three dimensions. While infrared near-field microscopy provides high sensitivity and nanoscopic spatial resolution two dimensions, quantitative extraction material properties three-dimensionally samples has not been achieved yet. Here we introduce a method to perform rapid recovery thickness permittivity simple 3D...
This work probes the relevance of oxygen vacancies in formation local ferromagnetic coupling between Fe ions at octahedral sites zinc ferrites. gives rise to a ferrimagnetic ordering with Curie temperatures above room temperature an otherwise antiferromagnetic compound. conclusion is based on experimental results from x-ray magnetic circular dichroism measurements $\mathrm{Fe}{\mathrm{L}}_{2,3}$ edges and magnetization performed ferrites, nanoparticles, films, different cation distributions...
We report magnetoresistance measurements on thin Pt bars grown epitaxial (001) and (111) CoFe2O4 (CFO) ferrimagnetic insulating films. The results can be described in terms of the recently discovered spin Hall (SMR). magnitude SMR depends interface preparation conditions, being optimal when Pt/CFO samples are prepared situ, a single process. spin-mixing conductance, key parameter governing other relevant spin-dependent phenomena, such as pumping or Seebeck effect, is found to different...
Abstract Being a facet of flexible electronics, mechanically reshapeable magnetic field sensorics enable novel device ideas for soft robotics, interactive devices virtual- and augmented reality point care diagnostics. These applications demand compliant yet robust sensor revealing high sensitivity to small fields. To push the detection limit highly linear sensors be in sub-µT range, we explore new fundamental concept sensing, namely planar Hall effect thin films. With their remarkable...
Resistance random access memory (ReRAM) is considered a promising candidate for the next generation of non-volatile memory. In this work, we fabricate Co/HfO2/Ti devices incorporating atomic-layer-deposited HfO2 thin films as active material grown under different atomic layer deposition (ALD) conditions. We focus on analyzing effect ALD conditions resistive switching behaviour devices. Electrical characterization reveals particular non-crossing current–voltage curve and bipolar behaviour....
Silicon Photomultipliers (SiPMs) are optical sensors widely used in space applications due to their high photon detection efficiency, low power consumption, and robustness. However, Low Earth Orbit (LEO), performance degrades over time prolonged exposure ionizing radiation, primarily from trapped protons electrons. The dominant radiation-induced effect SiPMs is an increase dark current count rate, which can compromise detector sensitivity. This study investigates the potential of thermal...
X-ray absorption near-edge and grazing incidence x-ray fluorescence spectroscopy are employed to investigate the electronic structure of ZnFe${}_{2}$O${}_{4}$ thin films. The techniques used determine nonequilibrium cation site occupancy as a function depth oxygen pressure during deposition its effects on magnetic properties. It is found that low pressures below 10${}^{\ensuremath{-}3}$ mbar cause iron superoccupation tetrahedral sites without Zn${}^{2+}$ inversion, resulting in an ordered...
We directly visualize and identify the capacitive coupling of infrared dimer antennas in near field by employing scattering-type scanning near-field optical microscopy (s-SNOM). The is identified (i) resolving strongly enhanced nano-localized fields antenna gap (ii) tracing red shift resonance when compared to single constituents. Furthermore, modifying illumination geometry we break symmetry, providing a means excite both bonding "dark" anti-bonding modes. By spectrally matching modes,...
We test the validity of Hanle measurements in three-terminal devices by using aluminum (Al) and gold (Au). The obtained inverted Hanle-like curves show an anomalous behavior. First, we measure signals 8 orders magnitude larger than those predicted standard theory. Second, temperature voltage dependences signal do not match with tunneling spin polarization ferromagnetic contact. Finally, relaxation times this method are independent choice metallic channel. These results compatible...
Commercial LaAlO3 substrates were thermally cycled simulating a procedure similar to those followed during TiO2 and SnO2 dilute magnetic semiconductors’ film pulsed laser deposition. Ferromagneticlike behavior was found in some substrates, which metallic iron impurities detected by x-ray photoelectron spectroscopy total reflection fluorescence measurements. A thorough experimental investigation, using high resolution techniques, showed that these introduced the used fix oven silicon holders....
Over the past three decades, acceptance of higher risk thresholds within space industry has facilitated widespread integration commercial off-the-shelf (COTS) components into avionics and payloads, leading to a remarkable transformation in design missions. This led emergence New Space Economy adoption lean or small satellites general, particularly CubeSats. CubeSats are now widely used commercial, scientific, research applications due their versatility, affordability, simplicity development,...
A C60-based magnetic tunnel transistor is presented. The device based on the collection of spin-filtered hot-electrons at a metal/C60 interface, and it allows an accurate measurement energy level alignment such interface. 89% change in collected current under application field demonstrates that these devices can be used as sensitive sensors compatible with soft electronics.