Laser-Field Induced Ultrafast Optical Responses of e-h Plasmas in Dipole-Radiation-Coupled Double Quantum Dots*

By employing quantum-kinetic semiconductor-Bloch equations, we study the ultrafast-optical responses of photo-generated e-h plasmas in electromagnetically-coupled double quantum dots, and demonstrate the physics mechanism involved in laser-controlled nonlinear-optical response of e-h pairs. For a single-dot system, we perform numerical computation for displaying transient dynamics in occupations and quantum coherence of e-h pairs under a laser pulse. For a double-dot system with dipole-radiation coupling, on the other hand, we analyze transient dynamics of both intra-dot and inter-dot depolarization fields. Additionally, we reveal the significance of phase matching between depolarization and laser fields in maximizing stimulated transitions of e-h pairs. Our physics model and numerical-computation method enable designing and developing artificial quantum molecules, including arbitrarily located quantum dots with non-local quantum interactions and entanglement, as well as optically-manipulating electronic states of artificial quantum molecules.