Phase Control of Transient Optical Properties of Quantum-Dot Nanostructure via Terahertz Signal Radiation

We theoretically analyze the transient properties of a probe field absorption dispersion in a quantum-dot nanostructure driven by terahertz signal radiation. Here a four-level quantum-dot nanostructure is designed numerically by Schr?dinger and Poisson's equations. We show that in the presence of the THz signal, the medium becomes phase dependent and the absorption dispersion can be dramatically influenced by the relative phase between applied fields.