A5021672302- Magnetic properties of thin films
- Magnetic Properties and Applications
- Advanced Memory and Neural Computing
- Magneto-Optical Properties and Applications
- Quantum and electron transport phenomena
- Physics of Superconductivity and Magnetism
- Ferroelectric and Negative Capacitance Devices
- Electric Motor Design and Analysis
- Phase-change materials and chalcogenides
- Advanced Data Storage Technologies
- Magnetic and transport properties of perovskites and related materials
- Semiconductor materials and devices
- ZnO doping and properties
- Characterization and Applications of Magnetic Nanoparticles
- Copper Interconnects and Reliability
- Magnetic Field Sensors Techniques
- Theoretical and Computational Physics
- Magnetic Properties of Alloys
- Metallic Glasses and Amorphous Alloys
- Advanced Electron Microscopy Techniques and Applications
- Metal and Thin Film Mechanics
- Neural Networks and Reservoir Computing
- Orbital Angular Momentum in Optics
- Atomic and Subatomic Physics Research
- Error Correcting Code Techniques
Spintronique et Technologie des Composants
2016-2025
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2016-2025
CEA Grenoble
2016-2025
Institut polytechnique de Grenoble
2013-2024
Université Grenoble Alpes
2015-2024
Centre National de la Recherche Scientifique
2015-2024
Institute of Electrical and Electronics Engineers
2021-2024
Antea Group (France)
2023-2024
Conference Board
2023-2024
Alpha Omega Electromagnetics (United States)
2020-2023
Spintronics is one of the emerging fields for next-generation nanoelectronic devices to reduce their power consumption and increase memory processing capabilities. Such utilise spin degree freedom electrons and/or holes, which can also interact with orbital moments. In these devices, polarisation controlled either by magnetic layers used as spin-polarisers or analysers via spin–orbit coupling. Spin waves be carry current. this review, fundamental physics phenomena described first respect...
Magnetism is a very fascinating and dynamic field. Especially in the last 30 years, there have been many major advances range of areas from novel fundamental phenomena to new products. Applications such as hard disc drives magnetic sensors are part our daily life applications, non-volatile computer random access memory, expected surface shortly. Thus it an opportune time for describing current status future challenges form roadmap article. The 2014 Roadmap provides view on several selected,...
Ever since the first observation of all-optical switching magnetization in ferrimagnetic alloy GdFeCo using femtosecond laser pulses, there has been significant interest exploiting this process for data-recording applications. In particular, ultrafast speed magnetic reversal can enable writing speeds associated with memory devices to be potentially pushed towards THz frequencies. This work reports development perpendicular tunnel junctions incorporating a stack Tb/Co nanolayers whose...
Magnetic random access memories (MRAMs) are a new non-volatile memory technology trying establish itself as mainstream technology. MRAM cell operation using thermally assisted writing scheme (TA-MRAM) is described in this review well its main design challenges. This approach compared to conventional MRAM, highlighting the improvements write selectivity, power consumption and thermal stability. The TA-MRAM was tested validated dynamic regime down 500 ps pulses. heating process investigated...
This paper is focused on thermally assisted magnetic random access memories (TA-MRAMs). It explains how the heating produced by Joule dissipation around tunnel barrier of junctions (MTJs) can be used advantageously to assist writing in MRAMs. The main idea apply a pulse junction simultaneously with field (field-induced (TA) switching). Since current also provides spin-transfer torque (current-induced TA switching), lines removed increase storage density TA-MRAMs. Ultimately, induced...
A new approach to increase the downsize scalability of perpendicular STT-MRAM is presented.
A thermally assisted writing procedure is proposed in a tunnel junction based magnetic random access memory cell. The layers of the are both exchange-biased with antiferromagnetic layers, reference layer having much higher blocking temperature than storage layer. In operating mode, current pulse sent through generates enough heat to raise above its temperature, without affecting pinning concept demonstrated here for an isolated using homogeneous external field.
We report on the experimental evidence of magnetic helicoidal dichroism, observed in interaction an extreme ultraviolet vortex beam carrying orbital angular momentum with a vortex. Numerical simulations based classical electromagnetic theory show that this dichroism is interference light modes different momenta, which are populated after between and topology. This observation gives insight into interplay magnetism sets framework for development new analytical tools to investigate ultrafast...
Nucleation and annihilation of vortex states have been studied in two-dimensional arrays densely packed cobalt dots. A clear signature dipolar interactions both between single-domain state dots has observed from the dependence nucleation fields on interdot separation. direct consequence these is formation chains as well dipole aligned along direction external field. In addition, short range correlation chiralities within using magnetic force microscopy imaging attributed to cross-talking...
In magnetic tunnel junctions (MTJ), synthetic antiferromagnets (SAF) are usually used as reference layer to minimize dipolar interactions induced between this and the free (FL). We show here that use of SAF allows us reduce asymmetry FL reversal due stray fields in nanosized MTJs with perpendicular anisotropy.
Spin-electronics is a very rapidly expanding area of R&D which merges magnetism and electronics (Nobel Prize 2007). Since the discovery giant magnetoresistance in 1988, several breakthroughs have further boosted this field (spin-valves 1990, tunnel 1995, spin transfer 1996, voltage controlled magnetic properties 2004). The phenomenon spin-transfer particularly attractive both from fundamental applied view points. It provides new way to manipulate magnetisation nanostructures by...
Abstract We report here the development of Pt and Pd-free perpendicular magnetic tunnel junctions (p-MTJ) for STT-MRAM applications. start by studying a p-MTJ consisting bottom synthetic Co/Pt reference layer FeCoB/Ru/FeCoB storage covered with an MgO layer. first investigate evolution RKKY coupling Ru spacer thickness in such The becomes antiferromagnetic above 0.5 nm its strength decreases monotonously increasing thickness. This contrasts behavior Co-based systems which maximum interlayer...
This work reports the development of perpendicular magnetic tunnel junctions, based on a multilayered stack [Tb/Co] nanolayers, in which magnetization can be reliably toggled using single optical pulse. The helicity-independent single-shot switching Tb/Co was achieved either 60 fs-long or 5 ps laser pulses with incident fluences down to 4.7 mJ/cm2. for Co-rich composition window multilayer corresponding layer thickness ratios tCo/tTb between 1.3-1.5. confirmed alone as well coupled aCoFeB...
This paper reports sub-nanosecond precessional spin-transfer switching in elliptical magnetic tunnel junction nanopillars. result is obtained samples integrating a synthetic antiferromagnetic perpendicular polarizer and with in-plane magnetized electrodes. The out-of-plane precession of the free layer magnetization results oscillations probability as function pulse width. At 9.25 MA/cm2 current density, these have period 1 ns high degree coherence.
The spatial and temporal dynamics of laser-induced single-shot magnetization switching are studied for various compositions Tb/Co multilayers to understand the underlying mechanism. This is shown be drastically different from ones in Tb-Co alloys as well previously toggle-switching Gd-containing ferrimagnets.
Abstract Single Pulse All Optical Switching represents the ability to reverse magnetization of a nanostructure using femtosecond single laser pulse without any applied field. Since first switching experiments carried out on GdFeCo ferrimagnets, this phenomena has been only recently extended few other materials, MnRuGa alloys and Tb/Co multilayers with very specific range thickness composition. Here, we demonstrate that can be obtained for large rare earth–transition metal multilayers, making...
A method to switch the magnetization of free layer in magnetic tunnel junctions with perpendicular anisotropy is demonstrated. It consists assisting spin transfer switching by a thermally induced reorientation from out-of-plane in-plane. The junction temperature increase due Joule dissipation around barrier produced same pulse current which generates torque. This allows torque efficiency be maximal since polarization layer. Such assisted designing highly down-size scalable magnetoresistive...
The state-of-the-art solid-state drives (SSDs) now heterogeneously integrate NAND Flash and dynamic random access memories (DRAMs) to partially hide the limitation of nonvolatile memory technology. However, due increased request for storage density coupled with performance that positions tier closer latency processing elements, are becoming a serious bottleneck. DRAM as well in SSD reliability their vulnerability power loss events. Several emerging technologies candidate replace them, namely...
A new concept to increase the downsize scalability of perpendicular spin transfer torque magnetic random-access memory (p-STT-MRAM), called shape anisotropy (PSA) STT-MRAM is presented. This approach consists significantly increasing thickness storage layer in p-STT-MRAM values comparable cell diameter so as induce a PSA this which comes on top MgO/FeCoB interfacial anisotropy. PSA-STT-MRAM provided by depositing thick ferromagnetic (FM) an based tunnel junction (MTJ) that becomes order or...
In this work the thermal heating of tunnel junctions is investigated doing one-dimensional numerical simulations by solving heat equation. The temperature increase proportional to power density jV, which confirmed transport measurements on patterned μm size junctions. observed was 2.3 K/(mW μm−2) compared a simulation result 0.9 μm−2). Tunneling AFM 4, 5.4, and 6.7 Å barrier half-junctions, show hot spots with current densities up 13 times average value. concentration could explain higher...
The perpendicular magnetic anisotropy (PMA) of Pt/CoFe(B)/MgO bottom electrodes and the tunnel magnetoresistance (TMR) CoFeB-based junctions (MTJ) have been analyzed as a function Mg thickness for naturally oxidized barriers. Low PMA TMR values are found over-oxidized (small MgO thickness) under-oxidized (large When CoFe is used electrode, strong correlation observed between variation with maxima in both quantities occurring an around 1.2 nm. On contrary, CoFeB electrodes, sensitivity to...