The integration of magnetic materials with semiconductors will lead to the development of the next spintronics devices such as spin field effect transistor (SFET), which is capable of both data storage and processing. While the fabrication and transport studies of lateral SFET have attracted greatly attentions, there are only few studies of vertical devices, which may offer the opportunity for the future three-dimensional integration. Here, we provide evidence of two-terminal electrical spin injection and detection in Fe/GaAs/Fe vertical spin-valves (SVs) with the GaAs layer of 50 nanometers thick and top and bottom Fe electrodes deposited by molecular beam epitaxy. The spin-valve effect, which corresponds to the individual switching of the top and bottom Fe layers, is bias dependent and observed up to 20 K. We propose that the strongly bias- and temperature-dependent MR is associated with spin transport at the interfacial Fe/GaAs Schottky contacts and in the GaAs membranes, where balance between the barrier profiles as well as the dwell time to spin lifetime ratio are crucial factors for determining the device operations. The demonstration of the fabrication and spin injection in the vertical SV with a semiconductor interlayer is expected to open a new avenue in exploring the SFET.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4949422 | PMC |
http://dx.doi.org/10.1038/srep29845 | DOI Listing |
J Phys Condens Matter
September 2024
Functional Thin Films Laboratory, Department of Physics, School of Physical, Chemical and Applied Sciences, Pondicherry University, Kalapet, 605014 Puducherry, India.
Spin injection across 160 nm thick semi-crystalline Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) is methodically investigated at room temperature in PVDF-HFP/NiFe bilayers and Ag/(NiFe or Co)/PVDF-HFP/NiFe vertical organic spin valves (OSVs) using both the co-planar waveguide ferromagnetic resonance (CPW-FMR: 7-35 GHz) and magnetoresistance (MR) techniques. The structural and microstructural characteristics of PVDF-HFP reveal the formation of mixed non-ferroelectric alpha and ferroelectric beta phases. The spin injection due to the transfer of angular momentum in PVDF-HFP/NiFe is quantified by measuring the spin-mixing conductance () and the enhancement in Gilbert damping () parameters from CPW-FMR data.
View Article and Find Full Text PDFSmall
October 2023
Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang, 315201, China.
ACS Appl Mater Interfaces
December 2022
National University of Science and Technology MISiS, 4 Leninskiy Prospect, Moscow119049, Russian Federation.
Integration of half-metallic materials and 2D spacers into vertical magnetoresistive spin valves may pave the way for effective low-power consumption storage and memory technologies. Driven by the recent successful growth of graphene/half-metallic CoFe(GeGa) (CFGG) heterostructure, here we report a theoretical investigation of magnetic tunnel junction (MTJ) based on the ferromagnetic CFGG Heusler alloy and the MoS spacer of different thicknesses. Using approach, we demonstrate that the inherent ferromagnetism of CFGG is preserved at the interface, while its half-metallicity is recovering within few atomic layers.
View Article and Find Full Text PDFACS Nano
August 2022
Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China.
Two-dimensional (2D) magnets are crucial in the construction of 2D magnetic and spintronic devices. Many devices, including spin valves and multiple tunneling junctions, have been developed by vertically stacking 2D magnets with other functional blocks. However, owing to limited local interactions at the interfaces, the device structures are typically extremely complex.
View Article and Find Full Text PDFSci Rep
January 2021
Instituto de Engenharia de Sistemas e Computadores - Microsistemas e Nanotecnologias (INESC-MN), 1000-029, Lisbon, Portugal.
A new device architecture using giant magnetoresistive sensors demonstrates the capability to detect very low magnetic fields on the pT range. A combination of vertically packed spin-valve sensors with two-dimensional in-plane arrays, connected in series and in parallel, delivers a final detection level of 360 pT/[Formula: see text] at 10 Hz at room temperature. The device design is supported by an analytical model developed for a vertically packed spin-valve system, which takes into account all magnetic couplings present.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!