Phonon drag effect

Author: bnqf

August undefined, 2024

WebThe effect of isotopic impurities on the phonon modes of polyatomic crystals is discussed theoretically. The diagonalized mass-independent force matrix can be considered as force, and the square of the phonon frequency as acceleration, so that the remaining coefficient, which is only related to the atomic mass, can be regarded as effective mass. WebJan 31, 2002 · It has been predicted that the phonon drag thermopower will be enhanced in very low mobility samples. The effect occurs when ql No full-text available Citations (19) ... At relatively low...

Colossal Seebeck effect enhanced by quasi-ballistic phonons

WebThe Fig.1: Variation of Thermopower S with Carrier reduction in SiGe alloy NWs came from the phonon alloy Concentration (Ns) scattering which scatters short wavelength phonons with high frequency, while low frequency phonons are scattered Figure 1 show our calculations from equation (2) by the phonon boundary scattering. WebMar 31, 2024 · In this work, we systematically examine the phonon drag effect, namely the momentum exchange between nonequilibrium phonons and electrons, and its impact on charge mobility and Seebeck coefficient in GaN and AlN by solving the fully coupled electron and phonon Boltzmann transport equations with ab initio scattering parameters. We find … how many people born in 1926 are still alive

Transient hot-phonon effects on the velocity overshoot of GaAs: A …

WebDec 15, 2024 · Drag also strongly boosts the intrinsic electron mobility, thermal conductivity and the Lorenz number. Impurity scattering is seen to suppress the drag enhancement of … WebMay 13, 2014 · Phonon-drag effect in FeGa3. The thermoelectric properties of single- and polycrystalline FeGa3 are systematically investigated over a wide temperature range. At … WebNov 30, 2024 · Since phasons can be considered an ultimate phonon drag effect, it is of interest to see its effects on thermoelectricity, which is studied in the present paper based on linear response theory of Kubo and Luttinger. how many people born in 1947 are still alive

Phonon-engineered extreme thermal conductivity materials

Phonon - an overview ScienceDirect Topics

WebApr 13, 2024 · The effect of phonon focusing on the drag thermopower and lattice thermal conductivity of bulk potassium crystals and nanostructures based on it was analyzed, and the spectrum and polarization vectors of phonons were determined in [1–4].In these studies, when analyzing the thermopower and lattice thermal conductivity, it was assumed that … WebMar 9, 2024 · Abstract It has been known for more than a decade that phonons can produce an off-diagonal thermal conductivity in the presence of a magnetic field. Recent studies of thermal Hall conductivity, κxy, in a variety of contexts, however, have assumed a negligibly small phonon contribution. how can i find out what city i was born inWebIn our opinion this assumption is questionable. The analysis reported here includes the phonon-drag component S g of thermoelectric power using the balance equation approach, which has the advantage of easy inclusion of hot electron effects. In this, we clarify the importance of the contribution of S g to thermoelectric power in the hot-electron transport … how can i find out the price a house sold for

"WebPhonon drag is an increase in the effective mass of conduction electrons or valence holes due to interactions with the crystal lattice in which the electron moves. As an electron moves past atoms in the lattice its charge distorts or polarizes the nearby lattice. " - Phonon drag effect

Phonon drag effect

WebDec 29, 2014 · We present a theory of the phonon-drag Seebeck coefficient in nondegenerate semiconductors, and apply it to silicon for temperatures 30 < T < 300 K. Our calculation uses only parameters from the literature, and previous calculations of the phonon lifetime. We find excellent agreement with the measurements of Geballe and Hull …

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WebDec 29, 2014 · However, the Seebeck effect can also have a phonon drag component, due to momentum exchange between charge carriers and lattice phonons, which is more difficult to quantify. In this work, we present the first study of phonon drag in the AlGaN/GaN two-dimensional electron gas (2DEG). We find that phonon drag does not contribute … WebFeb 19, 2013 · The spin Seebeck effect refers to the generation of a spin voltage caused by a temperature gradient in a ferromagnet, which enables the thermal injection of spin currents from the ferromagnet into an attached nonmagnetic metal over a macroscopic scale of several millimeters.

WebNov 16, 2015 · It has been well known that the phonon drag effect—an extra electrical current induced by phonon heat flow via electron–phonon interaction—can lead to … WebMar 1, 2013 · Our analysis indicates that a significant phonon-drag effect must take place in coarse-grained samples at low temperature. As the grain size decreases, the phonon …

WebJul 16, 2024 · Thus, it is clarified that the roughness on the wire surface is an important factor for the phonon-drag effect in the Si Seebeck coefficient. Hence, for preserving the … WebHere, we focus on the phonon drag effect. Historically, a large Seebeck coefficient was observed in doped semiconductors such as Ge and Si, 6 – 8) which has been ascribed to …

WebAug 31, 2024 · The photon-drag (PD) effect is the rectified electrical current in a medium generated by radiation pressure. That is, the optical force delivered to an illuminated …

WebSep 6, 2016 · Phonon transport is an essential property of thermoelectric materials. Although the phonon carries heat, which reduces the thermoelectric efficiency, it contributes positively to the Seebeck coefficient S through the phonon-drag effect, as typified by the high-purity semiconductors, which show fairly large S at cryogenic temperatures. how many people born in 2022WebElectron–phonon interaction might also affect thermoelectric properties, for example, the Seebeck coefficient could also be enhanced through the phonon-drag effect 164. First-principles... how many people born in 1937 are still aliveWebSep 2, 2024 · The results of an investigation on tensile stress dependence of mean Seebeck coefficient in Fe-based amorphous ribbons are presented, constituting a new Seebeck-sigma effect. A measurement test stand, capable of the determination of small variations in thermopower in such materials under stress is described. Exemplary results for … how many people born in 1938 are still aliveWebApr 1, 1996 · The phonon-drag voltage induced by acoustic phonons has been studied for the first time in 2D hole gas (2DHG) systems, formed in GaAs/AlGaAs heterostructures. … how many people born every secondWebDec 15, 2024 · Drag also strongly boosts the intrinsic electron mobility, thermal conductivity and the Lorenz number. Impurity scattering is seen to suppress the drag enhancement of the thermal and electrical conductivities, while having weak effects on the enhancement of the Lorenz number and thermopower. how can i find out what i owe the irsWebApr 15, 2024 · Upon dynamic loading (strain rate at ~10 3 s −1), the strain rate effect of materials is mainly affected by the viscous-drag effect 1,19,59, i.e., the interaction between the dislocations and ... how many people born in 1940 are still aliveWebphonon modes contributing to carrier diffusion and phonon drag effect. The most efficient Thermoelectrics have been heavily doped semiconductors because the Pauli principle restricts the heat carrying electrons to within of the Fermi level for metals. Semiconductors have a lower density of carriers, leasing to larger thermopower values ... how many people born in 1899 are still alive