Theoretical research on the dynamics process and optical absorption spectra of semiconductor superlattice under the terahertz field

Abstract

Abstract:

Using an excitonic basis ,we take the density matrix theory to investigate the intraband dynamics process and optical absorption spectrum of semiconductor superlattice in Terahertz fields.The excitonic Bloch oscillation is driven by the Terahertz field .The slow variation in the intraband polarization depends on the Terahertz frequency, with the increase of Terahertz frequency, the intraband polarization does oscillation downwards and its intensity decrease. Taking and superlattices for examples, because of the nonlinear effect of Terahertz field and WSL excitons, their optical absorption spectrums take on satellite peak structures . However, when we compared these two superlattices in different states, we conclude that the optical absorption spectrum anastomoses well for the strong coupling effect between the excitonic state of n<0 and the state of n=0, while a red shift emerges in the state of n=0 and the sideband effect in the optical absorption spectrum is not very obvious in the state of n>0.

Key words: optical electronics, optical absorption spectrum, density matrix theory, semiconductor superlattice, THZ electromagnetic wave

CLC Number:

LI Min, MI Xian-Wu. Theoretical research on the dynamics process and optical absorption spectra of semiconductor superlattice under the terahertz field[J]. J4, 2009, 26(4): 482-488.

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