Theory of electron-plasmon-scattering rate in highly doped bulk semiconductors

Abstract

We compared two different formulations, the electron-field and electron-electron models, for electron-plasmon scattering in bulk semiconducting materials. The calculations employ three different expressions for the plasmon dispersion relation and are made at two different temperatures. It is found that the functional form of the dispersion relation greatly affects the electron-plasmon-scattering rate. The electron-field model is found to predict a higher scattering rate than the electron-electron model, independent of the form of the dispersion relation. Either model predicts the same order-of-magnitude scattering rate, which is found, in the case of bulk degenerate GaAs, to be comparable to the polar optical-phonon-scattering rate. Based on these calculations, plasmon scattering appears to be an important mechanism limiting electron transport in degenerate semiconductors and related semiconductor devices.

Electron mobility in monoclinic β-Ga2O3—Effect of plasmon-phonon coupling, anisotropy, and confinement

“…Plasmons are longitudinal vibrational modes of collective electrons. The vibrational energy of such oscillations in a bulk semiconductor under long-wavelength limit is given by [27]…”

“…We treat this effect (approximately) by turning off the plasmon mode in the EHC. The upper boundary of EHC is given by [27], 𝜔 + (𝑞) = ℏ 2 𝑘 𝐹 𝑞 𝑚 * + ℏ 2 𝑞 2 2𝑚 * , where 𝑘 𝐹 is the Fermi wavevector calculated at zero temperature. Due to isotropic conduction band minima, the upper boundary of EHC is taken to be isotropic in β-Ga2O3 and hence the plasmon damping is dependent only on the magnitude of q.…”

Scattering in GaAs for Fermi kinetics transport

“…As determined by zeros of the Lindhard dielectric function, plasma resonances generally have a significant dispersion, but for moderate densities and temperatures, the limit for small wave vector approaches the classical plasmon energy [7]. For simplicity, the Fermi kinetics model currently uses this value with no dispersion, and it defines a cutoff wave vector q c in terms of the Fermi surface [8].…”

“…For simplicity, the Fermi kinetics model currently uses this value with no dispersion, and it defines a cutoff wave vector q c in terms of the Fermi surface [8]. An electron-plasma field model [7], [9] can then be used to express the scattering rate as,…”

Simulation of hole-mobility in doped relaxed and strained Ge layers

“…Additionally, we neglect the plasmon dispersion, 43,44 this is justified since the Coulombic nature of the plasmon interaction means that "small" scattering angle is favored, and therefore the dispersion plays a negligible role under the conditions of interest here. 44 It can be seen in Fig.…”