Thermoelectric effects in spintronics are gathering increasing attention as a means of managing heat in nanoscale structures and of controlling spin information by using heat flow. Thermal magnons (spin-wave quanta) are expected to play a major role; however, little is known about the underlying physical mechanisms involved. The reason is the lack of information about magnon interactions and of reliable methods to obtain it, in particular for electrical conductors because of the intricate influence of electrons. Here, we demonstrate a conceptually new device that enables us to gather information on magnon-electron scattering and magnon-drag effects. The device resembles a thermopile formed by a large number of pairs of ferromagnetic wires placed between a hot and a cold source and connected thermally in parallel and electrically in series. By controlling the relative orientation of the magnetization in pairs of wires, the magnon drag can be studied independently of the electron and phonon-drag thermoelectric effects. Measurements as a function of temperature reveal the effect on magnon drag following a variation of magnon and phonon populations. This information is crucial to understand the physics of electron-magnon interactions, magnon dynamics and thermal spin transport.
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http://dx.doi.org/10.1038/nmat3201 | DOI Listing |
ACS Omega
January 2025
Key Laboratory of High Performance Ship Technology, Wuhan University of Technology, Ministry of Education, Wuhan 430063, China.
Wearable thermoelectric generator (TEG) can collect human body heat and convert it into electrical energy, achieving self-powering of the device and thus becoming a hot research topic at present. By utilization of three-dimensional spiral thin-film thermoelectric structures and passive radiation cooling methods, the heat transfer area can be increased and power generation can be enhanced. In order to study the effect of outdoor radiation cooling on the thermoelectric performance of spiral heating, as well as the TEG performance output under different external environments and circuit loads, this paper proposes a new three-dimensional coupled numerical model of the spiral thermoelectric wristband system with multiple physical fields.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Institute of Electric Power Engineering, Czestochowa University of Technology, Armii Krajowej 17, 42-200 Czestochowa, Poland.
During the heat treatment of round steel bars, a heated charge in the form of a cylindrically formed bundle is placed in a furnace. This type of charge is a porous granular medium in which a complex heat flow occurs during heating. The following heat transfer mechanisms occur simultaneously in this medium: conduction in bars, conduction within the gas, thermal radiation between the surfaces of the bars, and contact conduction across the joints between the adjacent bars.
View Article and Find Full Text PDFSmall
January 2025
Key Lab of Photovoltaic and Energy Conservation Materials, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei, 230031, P. R. China.
N-type BiTeSe(BTS) is a state-of-the-art thermoelectric material owing to its excellent thermoelectric properties near room temperatures for commercial applications. However, its performance is restricted by its comparatively low figure of merit ZT. Here, it is shown that a 14% increase in power factor (PF) (at 300 K) can be reached through incorporation of inorganic GaAs nanoparticles due to enhanced thermopower originating from the energy-dependent carrier scattering.
View Article and Find Full Text PDFFront Cardiovasc Med
January 2025
Department of Anesthesiology and Reanimation, Faculty of Medicine, Bezmialem Vakif University, Istanbul, Türkiye.
Aim: This study aimed to protect brain functions in patients who experienced in-hospital cardiac arrest through the application of local cerebral hypothermia. By utilizing a specialized thermal hypothermia device, this approach sought to mitigate ischemic brain injury associated with post-cardiac arrest syndrome, enhance survival rates, and improve neurological outcomes as measured by standardized scales.
Methods: A prospective, single-center cohort study was conducted involving patients aged ≥18 years who experienced in-hospital cardiac arrest and achieved return of spontaneous circulation (ROSC).
Adv Sci (Weinh)
January 2025
SKKU Advanced Institute of Nanotechnology (SAINT) and Department of Nano Science and Technology, Sungkyunkwan University, Suwon, 16419, Republic of Korea.
A novel additive method to boost the Seebeck coefficient of doped conjugated polymers without a significant loss in electrical conductivity is demonstrated. Perovskite (CsPbBr) quantum dots (QDs) passivated by ligands with long alkyl chains are mixed with a conjugated polymer in a solution phase to form polymer-QD blend films. Solution sequential doping of the blend film with AuCl solution not only doped the conjugated polymer but also decomposed the QDs, resulting in a doped conjugated polymer film embedded with separated ions dissociated from the QDs.
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