Jamal T. Manassah

Statistical quantum electrodynamics of resonant atoms

Abstract This paper reviews the quantum statistical electrodynamics of resonant atoms: (a) the theory treats within the same formalism the independent atom quantum electrodynamics and the many-atom effects; (b) special emphasis given by phenomena associated with aggregates of like atoms in which resonant interactions are possible. To make the paper useful to a wide class of readers we included some details of field theory within the text.

Simple Models of Self-Phase and Induced-Phase Modulation

Supercontinuum (Alfano and Shapiro, 1970) generation is the production of nearly continuous spectra by propagating intense picosecond and subpicosecond laser pulses through nonlinear media. Induced supercontinuum (Manassah et al., 1985; Alfano et al., 1986) is the superbroadening of the spectrum of a weak pulse due to the presence of a strong pulse propagating simultaneously with it in a nonlinear medium. These observable physical effects form the motivation for the study of self-phase and induced-phase modulation. This chapter examines, for some idealized simple models of the nonlinear material and incoming pulse, the amplitude, phase, geometric shape, and spectral distribution of an outgoing pulse on exiting from the nonlinear material for cases of both absent and present pump. The chapter is limited in scope and extent; it is confined to some analytical and semianalytical cases developed by the author and co-workers. Effects related to group velocity dispersion (GVD) are not generally included among our models.

Billiard ball echo model in the statistical quantum electrodynamics formalism

Abstract Using techniques of statistical quantum electrodynamics, the results of the billiard ball model for photon echo are reproduced and further generalized to include relaxation parameters within the same formalism.

Photon echo in direct gap semiconductor

Abstract Using statistical quantum electrodynamics techniques, we investigate photon echo in intrinsic direct transition semiconductor materials. Possible applications of this effect in ultrashort time measurements and optical digital computation are discussed.

Applications of Supercontinuum: Present and Future

Over the past two decades the supercontinuum light source has been extensively used in laser spectroscopy research such as inverse Raman scattering (Alfano and Shapiro, 1971), time-resolved induced absorption in liquids and solids (Alfano and Shapiro, 1971; Greene et al., 1978), primary vision processes (Doukas et al., 1980), energy transfer mechanisms in photosynthesis (Searle et al., 1978; hot carrier and exciton relaxation processes in semiconductors (von der Linde and Lambrich, 1979; Shank et al., 1982), and time-resolved multiplex coherent anti-Stokes Raman scattering (Goldberg, 1982), to name a few.

Transient effects of three photon pulses in resonant two-level atom systems

Abstract Using statistical quantum electrodynamics techniques, we compute the polarization of a two-level atom system following three pulses. Homogeneous and inhomogeneous broadening and pulse width are incorporated in the formalism. Phase conjugation by three-photon process is investigated.