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Coherent emission from two or more classical damped oscillators leads to an apparent violation of conservation of energy if the oscillators are assumed to emit independently. To resolve this apparent paradox, it is necessary to include effects related to cooperative decay, wherein each oscillator modifies the damping rate of the other oscillators. We show how these effects are included for two radiating oscillators and for a line of N oscillators. The relation between cooperative decay, optical coherent transients, and superradiance is discussed. [c] 2010 American Association of Physics Teachers. [DOI: 10.1119/1.3475686]

Three calculations of optical Faraday rotation are presented in which a linearly polarized field is incident on a medium of harmonic oscillators in the presence of a longitudinal magnetic field. The rotation of the plane of polarization of the field is evaluated using classical oscillators and the Lorentz force equation, quantum oscillators and the Heisenberg equations of motion, and quantum oscillators and a Schrodinger equation approach. It is shown that a simple argument, based on the assumption that a circularly polarized field drives either [DELTA]m=1 or [DELTA]m=-1 transitions on absorption (m is the magnetic quantum number), leads to an incorrect result for the Verdet constant. [c] 2010 American Association of Physics Teachers. [DOI: 10.1119/1.3266970]

The intensity of Rayleigh scattering is proportional to the number of scatterers in a dilute gas. In contrast, for liquids or solids at low temperatures, any lateral Rayleigh scattering can be suppressed significantly. Microscopically, it is not obvious why the lateral Rayleigh scattering is diminished as the density in the medium increases. We use simple exactly solvable models to show that the suppression of Rayleigh scattering is proportional to the ratio of the interparticle correlation length to the interparticle distance. The wavelength of the scattered radiation is much larger than both these quantities in many cases of interest and does not play an explicit role in the suppression of lateral Rayleigh scattering. [c] 2010 American Association of Physics Teachers. [DOI: 10.1119/1.3236688]

To illustrate the concept of the dynamic creation of static fields, the fields associated with the creation of a static point charge and a static point dipole between times t=0 and t = [tau]-are calculated. For the former the field is that of a static charge in all space once t> [tau]. For the static point dipole the field pattern consists of three zones once t > [tau]. An expanding sphere of radius r=c(t-[tau]) in which the field is that of a static dipole, a shell defined by c(t-[tau])< r< ct, containing both electric and magnetic intermediate and far field components, and the volume beyond the event horizon, r> ct, for which the fields vanish. Despite the fact that the electric field occupies an increasing volume in space with increasing time, the energy in the field is constant once the dipole has been created. This result is established explicitly for an arbitrary creation of the static dipole. [DOI: 10.1119/1.2787018]

Abstract: In a previous paper [Phys. Rev. A 72 (2005) 033415], it was shown that sub-Doppler cooling occurs in a standing-wave Raman scheme (SWRS) that can lead to reduced period optical lattices. These calculations are extended to allow for non-zero detuning of the Raman transitions. New physical phenomena are encountered, including cooling to non-zero velocities, combinations of Sisyphus and “corkscrew” polarization cooling, and somewhat unusual origins of the friction force. The calculations are carried out in a semi-classical approximation and a dressed state picture is introduced to aid in the interpretation of the results. [Copyright &y& Elsevier]