Towards ultrafast communications: nonlinear coupling dynamics & light-semiconductor interaction

摘要: This thesis deals with some specific problems concerning the processing of ultrashort optical pulses and their interaction semiconductors. It includes investigation pulse propagation coupling dynamics in nonlinear coupled waveguide, coherent incoherent processes light-semiconductor interactions, therewith arising nonlinearities. The subpicosecond waveguide is investigated chapter 2. new feature found that waveguide’s switching characteristics do not depend on profile, like a soliton, but product dispersion length coefficient. By investigating cascaded method for rectangular generation proposed. In one self-focusing self-defocusing channel, limiting demonstrated both continuous wave pulses. After general theory semiconductor electrical properties described discussed 3, we focus polarization dependence transitions. shown amplifier much better reproduced if weak valence band non-degeneracy introduced heterostructure SOA than when it simply attributed to confinement factor difference. 4, correlation between electron spin circular emitted light studied. We notice that, uniaxially strained bulk semiconductors, possible achieve high electrons certain parts energy spectrum by circularly polarized light. 5, induced transient birefringence semiconductors due an 6, time scale studied within model emphasizes coherence photo-excited electron-hole pair correlation. Based this model, quantum beats four mixing signal