We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorpt...We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorption and dispersion of the probe field can be dramatically influenced by the relative phase between applied fields and intensity of the Gaussian laser beams.Transient and steady-state behaviors of the probe field absorption and dispersion are discussed to estimate the required switching time.The estimated range is between 5-8 ps for subluminal to superluminal light propagation.展开更多
This paper concerns the approximate controllability of the initialboundary problem of double coupled semilinear degenerate parabolic equations.The equations are degenerate at the boundary,and the control function acts...This paper concerns the approximate controllability of the initialboundary problem of double coupled semilinear degenerate parabolic equations.The equations are degenerate at the boundary,and the control function acts in the interior of the spacial domain and acts only on one equation.We overcome the difficulty of the degeneracy of the equations to show that the problem is approximately controllable in L2 by means of a fixed point theorem and some compact estimates.That is to say,for any initial and desired data in L2,one can find a control function in L2 such that the weak solution to the problem approximately reaches the desired data in L2 at the terminal time.展开更多
This paper reports a detailed theoretical investigation of strain effects on the performance of electroabsorption optical modulators based on the asym- metric intra-step-barrier coupled double strained quantum wells ...This paper reports a detailed theoretical investigation of strain effects on the performance of electroabsorption optical modulators based on the asym- metric intra-step-barrier coupled double strained quantum wells （AICD-SQWs） active layer. For this purpose, the electroabsorption coefficient was calculated over a range of AICD-SQWs strain from compressive to tensile strain. Then, the extinction ratio （ER） and insertion loss parameters were evaluated from calculated electroabsorp- tion coefficient for transverse electric （TE） input light polarization. The results of the simulation suggest that the tensile strain from 0.05% to 0.2% strain in the wide quantum well has a significant impact on the ER and insertion loss as compared with compressive strain, whereas the compressive strain of the narrow quantum well from -0.5% to -0.7% strain has a more pronounced impact on the improvement of the ER and insertion loss as compared with tensile strain.展开更多
文摘We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorption and dispersion of the probe field can be dramatically influenced by the relative phase between applied fields and intensity of the Gaussian laser beams.Transient and steady-state behaviors of the probe field absorption and dispersion are discussed to estimate the required switching time.The estimated range is between 5-8 ps for subluminal to superluminal light propagation.
基金the National Natural Science Foundation of China(Grant Nos.11925105,11801211).
文摘This paper concerns the approximate controllability of the initialboundary problem of double coupled semilinear degenerate parabolic equations.The equations are degenerate at the boundary,and the control function acts in the interior of the spacial domain and acts only on one equation.We overcome the difficulty of the degeneracy of the equations to show that the problem is approximately controllable in L2 by means of a fixed point theorem and some compact estimates.That is to say,for any initial and desired data in L2,one can find a control function in L2 such that the weak solution to the problem approximately reaches the desired data in L2 at the terminal time.
文摘This paper reports a detailed theoretical investigation of strain effects on the performance of electroabsorption optical modulators based on the asym- metric intra-step-barrier coupled double strained quantum wells （AICD-SQWs） active layer. For this purpose, the electroabsorption coefficient was calculated over a range of AICD-SQWs strain from compressive to tensile strain. Then, the extinction ratio （ER） and insertion loss parameters were evaluated from calculated electroabsorp- tion coefficient for transverse electric （TE） input light polarization. The results of the simulation suggest that the tensile strain from 0.05% to 0.2% strain in the wide quantum well has a significant impact on the ER and insertion loss as compared with compressive strain, whereas the compressive strain of the narrow quantum well from -0.5% to -0.7% strain has a more pronounced impact on the improvement of the ER and insertion loss as compared with tensile strain.
