T-matrix approach to equilibium and nonequilibrium carrier-carrier scattering in semiconductors

Abstract

An analysis of strong-coupling effects in carrier-carrier scattering in electron-hole plasmas in semiconductors is presented. The conventional approach to scattering and dephasing rates is based on the Born approximation ͑a scattering cross section proportional to the square of the dynamically screened interaction potential͒, and is strictly valid only in the limit of the weakly coupled quantum plasma. Otherwise, strong correlations are expected to become important in the scattering quantities. Therefore, we perform a thorough analysis of scattering rates in the framework of the statically screened T-matrix ͑ladder͒ approximation. We solve the two-particle Schrödinger equation and provide explicit results for the carrier-carrier scattering rates in equilibrium as well as for optical excitation conditions. Numerical results for GaAs show evidence of significant deviations from the common Born approximation. Finally, dynamic screening effects are included approximately. ͓S0163-1829͑99͒01815-9͔

Electron-phonon equilibration in laser-heated gold films

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“…[3], guaranteeing the correct spin statistics of the resulting theory. The coupled equations of motion for the two fields are Dirac's and Maxwell's equations and have been discussed already by J. Schwinger [41] in the early 1950s (for a historic overview 11 To simplify the notation we consider a one-component plasma. 12 Apart from the spinor structureΨ(1), is fully analogous to the annhilation operator a k discussed above, the main difference being that the former acts on N-particle states in continuous configuration space and annihilates a particle at space point r. Similarly, the creation operator a † k has its correspondence in the adjoint spinorΨ.…”

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