On the Theory of the Dynamic Stark Effect and Franz‐Keldysh Effect in a Resonant Electromagnetic Radiation Field

Abstract

The influence of the electric field of a resonant laser radiation on the dielectric function of a three-band semiconductor model is investigated theoretically. The laser radiation is assumed to be in resonance with the transition between the two unoccupied bands of the model. The relative contributions of the dynamic Stark effect due to the interband coupling caused by the laser field and of the Franz-Keldysh effect due to the intraband coupling are discussed. The laser-radiation-induced change of the real part of the dielectric function is calculated. The corresponding result for the imaginary part is in agreement with an earlier result of other authors. Explicit line shapes for the change of the real andimaginary part of the dielectric function are given with parameter values chosen close to those of GaAs.Es wird der EinfluB des elektrischen Feldes eines Laserstrahls auf die DielektrizitLtsfunktion eines Drei-Band-Modell-Halbleiters theoretisch untersucht. Dabei wird angenommen, daB sich die Laserstrahlung in Resonanz mit dem Ubergang zwischen den beiden nichtbesetzten BLndern des Modells befindet. Die relativen Beitriige des dynamischen Stark-Effektes, der auf die durch das Laserfeld bedingte Interband-Kopplung zuruckzufiihren ist, und des Franz-Keldysh-Effektes, der durch die Intraband-Kopplung hervorgerufen wird, werden diskutiert. Es wird die Laserstrahl-induzierte Anderung des Realteils der Dielektrizitatsfunktion berechnet. Das entsprechende Ergebnis fur den Imaginarteil ist in Ubereinstimmung mit friiheren Ergebnissen anderer Autoren. Fur Parameterwerte, die denen von GaAs angepaIt sind, wird die Linienform der Anderung des Real-und Imaginlrteils der Dielektrizitatsfunktion explizit angegeben.

Two‐Photon Absorption via Deep Local Levels as Virtual Intermediate States in Semiconductors

“…Inserting (11) into (6) we obtain p-1 = my1 + m ; l ; f&) = 2 1 (P,,) 12/3m,Eg is the interband oscillator strength. For the donor states, in the equations the indexes have t o be ehanged : A + D and v -+ c. Expressions (13) and (18) in the particular case of a single-beam approximation hw = = hoL agree with the results of El61 after the correction of the misprints there. Some analogs of (18), but only of such Pk-component "with k-conservation", have been obtained in [14,151, while @,-processes are fully ignored, and in [7] they are "lost" during calculations.…”

“…In(13) and(18) the constants C, and C, are equal to Dimensions of the values are: hot, Ec in eV; m, p in m,;…”

Interaction of Semiconductors with a Strong Resonance Electromagnetic Field

“…The influence of a laser beam on optical properties of crystals due to the dynamic Stark effect has been studied theoretically in references [lo, 111. I n paper [12] the results of Perlin and Kowarsky for the imaginary part of the dielectric function are extended by including the Franz-Keldysh effect.…”