arXiv subjects

L. Patrone

Publications and source records attributed to L. Patrone.

4 recordsLinked to original sources

arXiv2020

LabOSat as a versatile payload for small satellites: first 100days in LEO orbit

In this work the first results obtained by LabOSat-01 platform are presented. This platform was designed for testing custom devices on board of small satellites. Two LabOSat-01 type boards were launched and placed into Low Earth Orbit (LEO) on May 30, 2016. We present here an analysis of data collected by one of these boards during the first days of mission. Total Ionization Dose results are compared with data acquired by LabOSat-01`s predecessor board, MeMOSat-01, launched in 2014.

physics.ins-det↗

arXiv2019

Forming Weakly Interacting Multi Layers of Graphene by using Atomic Force Microscope Tip Scanning and Evidence of Competition Between Inner and Outer Raman Scattering Processes Piloted by Structural Defects

We report on an alternative route based on nanomechanical folding induced by AFM tip to obtain weakly interacting multi-layer graphene (wi-MLG) from a chemical vapor deposition (CVD) grown single-layer graphene (SLG). The tip first cuts, then pushes and folds graphene during zigzag movements. The pushed graphene has been analyzed using various Raman microscopy plots: $A_D /A_G \times E_L{}^4$ vs $\Gamma_G$, $\omega_{2D}$ vs $\Gamma_{2D}$, $\Gamma_{2D}$ vs $\Gamma_G$, $\omega_{2D+/-}$ vs $\Gamma_{2D+/-}$, and $A_{2D-}/A_{2D+}$ vs $A_{2D}/A_G$. We show that the SLG in plane properties are maintained under the folding process and that a few tens of graphene layers are stacked, with a limited amount of structural defects. A blue shift of about 20 cm-1 of the 2D band is observed. The relative intensity of the 2D$_-$ and 2D$_+$ bands have been related to structural defects, giving evidence of their role in the inner and outer processes at play close to the Dirac cone.

cond-mat.mes-hall↗

arXiv2019

Large memcapacitance and memristance at Nb:SrTiO$_{3}$ / La$_{0.5}$Sr$_{0.5}$Mn$_{0.5}$Co$_{0.5}$O$_{3-\delta}$ Topotactic Redox Interface

The possibility to develop neuromorphic computing devices able to mimic the extraordinary data processing capabilities of biological systems spurs the research on memristive systems. Memristors with additional functionalities such as robust memcapacitance can outperform standard devices in key aspects such as power consumption or miniaturization possibilities. In this work, we demonstrate a large memcapacitive response of a perovskite memristive interface, using the topotactic redox ability of La$_{0.5}$Sr$_{0.5}$Mn$_{0.5}$Co$_{0.5}$O$_{3-\delta}$ (LSMCO, 0 $\leq$ $\delta$ $\leq$ 0.62). We demonstrate that the multi-mem behaviour originates at the switchable n-p diode formed at the Nb:SrTiO3/LSMCO interface. We found for our Nb:SrTiO$_{3}$/LSMCO/Pt devices a memcapacitive effect C$_{HIGH}$/C$_{LOW}$ ~ 100 at 150 kHz. The proof-of-concept interface reported here opens a promising venue to use topotactic redox materials for disruptive nanoelectronics, with straightforward applications in neuromorphic computing technology.

physics.app-ph↗

arXiv2007

Electrical Characterisation of Ultra-thin SAM Structures

The way of reduction of metal oxyde semiconductor (MOS) structures is going to reach limitations and new devices have to be explored as an alternative to MOS technology. Molecular electronic and more particularly self-assembly-molecular technique on silicon substrate gives interesting results as seen in the literature. We are going to study n-alkyltrichlorosilane grafting on oxidised silicon, characterise it macroscopically with ellipsometer and goniometry measurements, and down to microscopic scale with atomic force microscopy. Once the uniformity of the monolayer is verified (roughness of few Angströms) we have tested a sputtering method deposition to form aluminium dots onto the surface. Also metal-insulator-semiconductor diodes are tested measuring both leakage current between gate and substrate and capacitance-voltage. The sputtering method deposition can be improved in order to decrease the gate leakage current and we would like to test another evaporation method. Further application we want to study is gas sensors using conjugated organic films or synthetic polymers and concerns the drift current with gas absorption.

cond-mat.mtrl-sci↗