Department of Physics, Center for Spinelectronic Materials and Devices, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany.
Published: September 2015
AI Article Synopsis
Article Abstract
The spin Seebeck effect, the generation of a spin current by a temperature gradient, has attracted great attention, but the interplay over a millimetre range along a thin ferromagnetic film as well as unintended side effects which hinder an unambiguous detection have evoked controversial discussions. Here, we investigate the inverse spin Hall voltage of a 10 nm thin Pt strip deposited on the magnetic insulators Y3Fe5O12 and NiFe2O4 with a temperature gradient in the film plane. We show characteristics typical of the spin Seebeck effect, although we do not observe the most striking features of the transverse spin Seebeck effect. Instead, we attribute the observed voltages to the longitudinal spin Seebeck effect generated by a contact tip induced parasitic out-of-plane temperature gradient, which depends on material, diameter and temperature of the tip.
Inspired by the recently reported novel two-dimensional material BCP, we performed one-dimensional shearing along the zigzag direction to obtain four BCP nanoribbons with various edge atom combinations. An asymmetric hydrogen passivation scheme was employed to modulate the electronic properties and successfully open the band gap, especially the 2H-1H passivation with dihydrogenation and monohydrogenation at the top and bottom edges, respectively, achieving bipolar magnetic semiconductors with edge P-atoms contributing to the main magnetism. Furthermore, three crucial spin-polarized transmission spectra yielded a significant spin-dependent Seebeck effect (SDSE), displaying superior thermoelectric conversion capabilities by generating pure spin currents.
- The study explores the HfVZ (Z = Ga, In, Tl) Heusler alloy's properties using density functional theory, confirming its stability in the F-43m phase and highlighting its half-metallic ferromagnetism and ductility.
- Modified Becke-Johnson methods outperformed generalized gradient approximations in assessing the electrical structure, and the quasi-harmonic Debye model was utilized to analyze the alloys' thermodynamic stability under various temperatures and pressures.
- The research also evaluates the alloys' thermoelectric performance and optical properties, suggesting potential applications in spintronics, thermoelectrics, and optoelectronics, which could guide future developments in hafnium-based Heus
Magnetic tunnel junctions (MTJs) with ultrathin MgO tunnel barriers are at the heart of magnetic random-access memory (MRAM) and exhibit potential for spin caloritronics applications due to the tunnel magneto-Seebeck effect. However, the high programming current in MRAM can cause substantial heating which degrades the endurance and reliability of MTJs. Here, we report the thermal characterization of ultrathin CoFeB/MgO multilayers with total thicknesses of 4.
We report a significant enhancement in the thermoelectric power of PEDOT by fabricating a novel ternary composite film by incorporating BiTe and rGO. A series of five samples of PEDOT:PSS/BiTe/rGO ternary composite films were synthesized using a spin coating method and having different weight% (0.0, 0.
Ab-initio simulations using density functional theory (DFT) were employed to investigate the structural, mechanical, electronic, magnetic, optical, and thermoelectric properties of halide perovskites [Formula: see text] (X = Cl, Br, I). Structural optimization and mechanical stability assessments confirm the reliability of these perovskites in a hexagonal P[Formula: see text]mc symmetry. The stability of the ferromagnetic phase was validated through total crystal energy minimization via Murnaghan's equation of state.
