Theoretical study on terahertz wave detection and radiation based on semiconductor nano structures

We study the magnetic-field-modulated terahertz absorption spectra of a real GaAs quantum ring by calculating the photon-participated tunneling current, and present a possible way to realize tunable detection of terahertz fields. In another content of the paper, we explore the terahertz radiation from high order harmonic field in a coupled triple quantum dots driven by gigahertz waves, due to the availability of high power. Because of the lack of inversion symmetry of real coupled triple quantum dots, the harmonic spectra consist of both odd and even orders, which improve the efficiency of the terahertz wave radiation.