Long-lived quantum coherence in a two-level semiconductor quantum dot

Abstract

In this paper, we present an analytical solution for the system of two-level semiconductor quantum dot. In addition, we discuss the rates of the photon radiative and phonon radiationless transitions from the excited state (α12, α21) , the rate of processes of pure dephasing (γ) , the detuning parameter (Δ) and the Rabi frequency (Ω), on the atomic occupation probabilities (ρ11(t) and ρ22(t)) , the atomic population inversion (ρz(t)) , the purity (PA(t)) , the von Neumann entropy (S(t)) and the information entropies (H(σx) , H(σy) and H(σz)). We clearly observe the emergence of long-lived quantum coherence phenomenon in all the curves for some special cases of α12, α21, γ, Δ and Ω. Besides, the decay phenomenon is quite evident in the purity curves, which can be simply controlled by changing the values of α12, α21 and γ.