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Interband impact ionization and nonlinear absorption of terahertz radiations in semiconductor heterostructures

J. C. Cao
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Abstract

We have theoretically investigated nonlinear free-carrier absorption of terahertz radiation in InAs/AlSb heterojunctions. By considering multiple photon process and conduction-valence interband impact ionization (II), we have determined the field and frequency dependent absorption rate. It is shown that (i) electron-disorder scatterings are important at low to intermediate field, and (ii) most importantly, the high field absorption is dominated by II processes. Our theory can satisfactorily explain a long standing experimental result on the nonlinear absorption in THz regime.

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J. C. Cao. 2003-12-02. Interband impact ionization and nonlinear absorption of terahertz radiations in semiconductor heterostructures. https://doi.org/10.1103/physrevlett.91.237401

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