### STP799: Quantum Theory of Multiphoton Free Carrier Absorption At High Intensities in Compound Semiconductors

Jensen, B

*Boston University, Boston, Massachusetts*

Pages: 4 Published: Jan 1983

**Abstract**

Multiphoton absorption and emission, accompanied by scattering of free carriers in an intense radiation field, is treated by an extension of the theory of one photon free carrier absorption in polar semiconductors. The rate equation for m photon absorption, where m is a positive integer, is obtained from the equation of motion of the quantum density matrix. It is shown to be proportional to the mth power of the radiation intensity. The effect of the field on the electron during scattering is taken into account by using the exact wavefunctions of an electron in an intense radiation field in the calculation of the transition matrix elements. An expression for the average Joule heating per electron is found. A comparison with earlier treatments is given.

**Keywords:**

Compound semiconductor, free-carrier absorption, multiphoton absorption

**Paper ID:** STP37280S

**Committee/Subcommittee:** F01.02

**DOI:** 10.1520/STP37280S

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