Search results for "Intron"

Tuning Spin Current Injection at Ferromagnet-Nonmagnet Interfaces by Molecular Design.

2020

There is a growing interest in utilizing the distinctive material properties of organic semiconductors for spintronic applications. Here, we explore the injection of pure spin current from Permalloy into a small molecule system based on dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophene (DNTT) at ferromagnetic resonance. The unique tunability of organic materials by molecular design allows us to study the impact of interfacial properties on the spin injection efficiency systematically. We show that both the spin injection efficiency at the interface and the spin diffusion length can be tuned sensitively by the interfacial molecular structure and side chain substitution of the molecule.

Functional characterization of a peroxisome proliferator response-element located in the intron 3 of rat peroxisomal thiolase B gene.

2003

Expression of the rat peroxisomal 3-ketoacyl-CoA thiolase gene B is induced by peroxisome proliferators. Although a sequence element like a peroxisome proliferator-activated receptor (PPAR)-binding site is located in the promoter region of this gene, we previously found that this element is competent for the activation by hepatocyte nuclear factor-4, but not functional with PPARalpha. We describe here a new peroxisome proliferator-response element located in the intron 3 (+1422/+1434) that binds in vitro the PPARalpha/retinoid X receptor alpha heterodimer and confers the induction by PPARalpha in transfection assays. We propose a model of regulation of the rat thiolase B gene involving thos…

Long-distance spin-transport across the Morin phase transition up to room temperature in ultra-low damping single crystals of the antiferromagnet α-F…

2020

Antiferromagnetic materials can host spin-waves with polarizations ranging from circular to linear depending on their magnetic anisotropies. Until now, only easy-axis anisotropy antiferromagnets with circularly polarized spin-waves were reported to carry spin-information over long distances of micrometers. In this article, we report long-distance spin-transport in the easy-plane canted antiferromagnetic phase of hematite and at room temperature, where the linearly polarized magnons are not intuitively expected to carry spin. We demonstrate that the spin-transport signal decreases continuously through the easy-axis to easy-plane Morin transition, and persists in the easy-plane phase through …

Spin transport across antiferromagnets induced by the spin Seebeck effect

2018

For prospective spintronics devices based on the propagation of pure spin currents, antiferromagnets are an interesting class of materials that potentially entail a number of advantages as compared to ferromagnets. Here, we present a detailed theoretical study of magnonic spin current transport in ferromagnetic-antiferromagnetic multilayers by using atomistic spin dynamics simulations. The relevant length scales of magnonic spin transport in antiferromagnets are determined. We demonstrate the transfer of angular momentum from a ferromagnet into an antiferromagnet due to the excitation of only one magnon branch in the antiferromagnet. As an experimental system, we ascertain the transport acr…

Gradual phase transition from ferromagnetic tetragonal to antiferromagnetic cubic states in Mn Ga (1.80 ≤ x ≤ 3.03) thin films

2019

Abstract The structural, magnetic, and electronic properties of MnxGa thin films are investigated as varying the Mn composition (1.80 ≤ x ≤ 3.03). The variation of x in MnxGa films dramatically changes the crystal structure as well as the magnetic properties. With increasing x, we observe the gradual phase transition from a ferromagnetic tetragonal state to an antiferromagnetic cubic state. The structural characterization reveals that the D022 tetragonal structure of Mn2Ga is slowly transformed to the L12 cubic structure of Mn3Ga. Two phases coexist around x = 2.4. The magnetization is systematically reduced as x increases, ending to an antiferromagnetic state of cubic Mn3Ga, and the electr…

Structure of the phenylalanine hydroxylase gene in Drosophila melanogaster and evidence of alternative promoter usage.

1996

The complete Drosophila melanogaster phenylalanine hydroxylase gene isolated from a genomic library was sequenced. Gene structure consisted of five exons covering a region of around 3 kb. Position of introns in the C-terminal domain was conserved with mammalian aromatic amino acid hydroxylase genes. Putative promoter sequences in the 5'UTR and intron 1 were identified. A novel transcript was detected differing from that previously reported by the inclusion of a part of the intron 1 sequence. It could be produced using an alternative promoter. The deduced open reading frame would code a protein with a small difference at the N-terminus. Expression of the alternative transcripts was examined …

Self-assembled monolayers based spintronics: from ferromagnetic surface functionalization to spin-dependent transport.

2016

Chemically functionalized surfaces are studied for a wide range of applications going from medicine to electronics. Whereas non-magnetic surfaces have been widely studied, functionalization of magnetic surfaces is much less common and has almost never been used for spintronics applications. In this article we present the functionalization of La2/3Sr1/3MnO3, a ferromagnetic oxide, with self-assembled monolayers for spintronics. La2/3Sr1/3MnO3 is the prototypical half-metallic manganite used in spintronics studies. First, we show that La2/3Sr1/3MnO3 can be functionalized by alkylphosphonic acid molecules. We then emphasize the use of these functionalized surfaces in spintronics devices such a…

Importance of Spin-Orbit Interaction for the Electron Spin Relaxation in Organic Semiconductors

2013

Despite the great interest organic spintronics has recently attracted, there is only a partial understanding of the fundamental physics behind electron spin relaxation in organic semiconductors. Mechanisms based on hyperfine interaction have been demonstrated, but the role of the spin-orbit interaction remains elusive. Here, we report muon spin spectroscopy and time-resolved photoluminescence measurements on two series of molecular semiconductors in which the strength of the spin-orbit interaction has been systematically modified with a targeted chemical substitution of different atoms at a particular molecular site. We find that the spin-orbit interaction is a significant source of electro…

Advances in Semiconductor Research: Physics of Nanosystems, Spintronics and Technological Applications

2014

Linear and nonlinear spin dynamics in multi-domain magnetoelastic antiferromagnets

2021

Antiferromagnets have recently surged as the prominent material platform for the next generation spintronics devices. Despite the remarkable abundance of antiferromagnets and the variety of their spin textures in nature, they share a widely common, if not ubiquitous, feature. Magnetoelasticity, which is expressed as strictions of different origin, relativistic and/or exchange, significantly contributes to the magnetic anisotropy of antiferromagnets. Crucially, a general theoretical framework able to address the role of domain walls on the spin dynamics in antiferromagnets in the presence of magnetoelasticity is lacking. Here we tackle this problem developing a very general macroscopic pheno…