LSV-SIE · The role of surface scattering and impurities in metallic lateral Spin-valve Devices
FP7 — People (Marie Curie Actions)
- Duration
- 2010-09-01 → 2014-08-31
- EU contribution
- €100,000
- Participants
- 1
- Scheme
- MC-IRG
Lines connect the coordinator with its partners.
Results in brief
The role of surface scattering and impurities in metallic lateral Spin-valve Devices
The research is placed in the field of spintronics, aimed at utilizing both the spin and charge degrees of freedom in electronic devices, in order to realize novel physics and functionalities. Spintronics devices have had technological impact, such as GMR high density memory. Preparation and study of multi-terminal ‘lateral’ architecture spin-devices opens many opportunities for research and applications, and is in the basis of our research. The long term goals, starting with the “LSV-SIE” project, are to identify and understand the relevant physical laws governing spin injection, propagation and interactions in lateral devices as function of material properties and geometrical architecture. Most lateral spin-devices make use of metallic ferromagnetic (FM) materials with easy (stable) magnetization direction in-plane. Magnetic material with perpendicular magnetization anisotropy (PMA) are advantages since they show magnetic stability also at the nano-scale. Our aim was to integrate PMA materials into lateral spin valves and study different contributions due to the new materials and the perpendicular geometry, enabling to realize new spin related phenomena, e.g. the ‘spin Hall effect’. During the funding period I: 1. Developed material deposition methods for FM and other materials. 2. Developed nanolithography and clean room fabrication processes. 3. Set-up variable temperature and magnetic field measurement system and precision electronics. 5. Studied the magnetic properties and spin injection as function of materials and geometry. We prepare high quality PMA multilayers such as Co/Pt or CoFeAl/Pd, each layer less than ~1nm repeated about x20. These materials are of interest in themselves. We identified a change in resistance with magnetic field that was not known for the materials and a refinement method to effectively measure the magnetization properties (published in JAP). This motivated us to study Pt/Co/Pt layers with ultra-thin cobalt, ~1-3 unit-cells. By measuring the ‘anomalous Hall effect’ we discovered unexpected variations in the magnetic exchange interactions. (Summarizing results for publication). We fabricated and measured properties of spin-devices with PMA electrodes, and characterized the efficiency of these materials as a spin source. Additionally we found interesting thermal effects, related to the perpendicular properties (published in APL and JAP). We have presented the results of the project in scientific meetings including the American Physical Society; the Israeli Physical society and in scientific seminars in Israel, Spain and the USA. This integration period has enabled me to set up a high functioning lab, recruit students and place me in an excellent position to attain a tenure position in my institute. It has enabled me to continue work on state of the art research, where we are studying the spintronics properties of novel and interesting 2D layered materials such as MoS2 (in collaboration with experts in the field).
Data: CORDIS, © European Union
Project objective
The field of spintronics is receiving continuous and growing attention, due to the expected increase in functions of lateral spintronics devices to include promising elements such as nonvolatile spin field effect transistors, ultra-fast memories and spin-based quantum computers.But, in order to utilize such lateral applications in industrial settings, a critical improvement in their performance is necessary, for which much basic research is still required. An important issue, which is relevant to the nano-scale lateral devices and has not received much attention, is surface effects. Here, spin scattering from the surface can lead to loss of all spin signals. The study and understanding of spin scattering, due to surface effects is one of the major goals of the proposed research.The study of lateral spintronics devices has led to discovery of many new phenomena; include spin transfer torque; crossed Andreev reflections and the spin Hall Effect. In the latter, anisotropic spin dependent scattering in non-magnetic materials induce a transverse spin current. This enables the generation of spin polarized currents in non-magnetic material without the need of injection from a ferromagnet. But, a larger magnitude of the effect is vital if one considers this a realistic source of spin-polarized current for application. We aim at increasing the spin Hall effect in metallic spintronics devices by resolving quantitatively the geometrical and material related contributions of the effect.Study of these spin transport phenomena via local probe measurements is a very powerful approach, as has been demonstrated for semiconductors using optical methods. We intend to develop and measure the local spin accumulation by an MFM-based measurement with an anticipated ~10 nm spatial resolution. This is x100 better than previous measurements, and will enable us to spatially resolve the local spin accumulation in metallic devices.
Original text from CORDIS.
Participants
- BAR ILAN UNIVERSITY · Ramat GanCoordinatorIsrael
Links
Data: CORDIS, © European Union