Heterojunction Bipolar Transistor with an Additional Minority Carrier Reflection Barrier in the Emitter

Abstract

We report values for the single-photoionization cross sections to the 3 S and 3 P o channels and for the total double photoionization cross section, σ ++ (E), of the metastable He − 1s2s2p 4 P o state, obtained from the implementation of the state-specific, complex eigenvalue many-electron, many-photon theory (MEMPT). The σ ++ (E) rises from 0 at E = 0 to a maximum of about 1.0 × 10 −20 cm 2 at E ∼ 3-5 eV and dies out around 30 eV. For this quantity, comparison with the measurements of Bae et al for E = 0.0-0.4 eV and with the semiclassical calculations of Crothers and Lennon, reveals disagreement. The effect of initialstate correlation in this case is quantitative but not qualitative.