Electron Subband Structure and Mobility Trends in P-N Delta-Doped Quantum Wells in Si

Abstract

Abstract-We present the electronic spectrum of a n-type deltadoped quantum well in Si coupled to a p-type delta-doped barrier within the envelope function effective mass approximation. We applied the Thomas-Fermi approximation to derive an analytical expression for the confining potential, and thus, we obtain the electronic structure in a simple manner. We analyzed the electron subband structure varying the distance between the doping planes (l) as well as the impurity density in them (n 2D , p 2D ). We also study the mobility trends through an empirical formula that is based on the electron levels, the electron wave functions and the Fermi level. We find a monotonic decrease in the mobility as the p-type barrier moves away from the n-type well, and optimum parameters, l = 70Å and n 2D = 5 × 10 12 cm −2 and p 2D = 5 × 10 13 cm −2 , for maximum mobility.

Calculation Absorption Coefficient of a Weak Electromagnetic Wave by Confined Electrons in Cylindrical Quantum Wires in the Presence of Laser Radiation by Using the Quantum Kinetic Equation

“…In this section, the ACF is numerically calculated for the specific case of GaAs/GaAsAl CQW. The parameters used in the calculations are as follows [8,25]: χ ∞ = 10.9, χ 0 = 13.1, m * = 0.066m 0 , m 0 being the mass of free electron, n 0 = 10 23 m −3 , ω 0 = 36.25 meV, α 1 = π 3 , α 2 = π 6 . Figure 1 describes the dependence of α on the temperature T for five different values of E 01 , with Ω 1 = 3 × 10 13 Hz, Ω 2 = 10 13 Hz, R = 30 nm.…”

Negative Absorption Coefficient of a Weak Electromagnetic Wave Caused by Electrons Confined in Rectangular Quantum Wires in the Presence of Laser Radiation Modulated by Amplitude

“…The parameters used in the calculations are as follows [13]: χ ∞ = 10.9, χ 0 = 13.1, m * = 0.066m 0 , m 0 being the mass of free electron, n 0 = 10 23 m −3 , ω 0 = 36.25 meV, Figure 1, we see that there are the temperature regions at which the ACF of a weak EMW in the presence of laser radiation modulated by amplitude is smaller than one in the presence of non-modulated laser radiation and that there are the temperature regions at which the ACF of a weak EMW in the presence of laser radiation modulated by amplitude gets values greater than one for the case of non-modulated laser radiation. In addition, ACF can gets negative values, i.e., ACF of a weak EMW becomes increased coefficient of a weak EMW.…”