We study theoretically the properties of a polaron formed in a shallow, weakly elliptical, disk-shaped InAs/GaAs quantum dot in the presence of a magnetic field by using the Davydov's canonical transformation. Special attention is paid to the energy-level splitting due to the Frohlich interaction of an electron in a quantum dot with optical phonons near resonance. The polaron relaxation rates, including the anharmonicity induced channel, are analyzed for various confinement energies and magnetic field magnitudes, taking into account coherent polaronic effects.

Magnetopolaron in a weakly elliptical InAs/GaAs quantum dot

Coherent Processes in Molecular Crystals

The 4000 Å transition of crystal anthracene

Summary


We present a quantum-field theoretical model to explain the experimentally suggested spatial localization of photons associated with the coherent state of phonons in an optical near-field probe system. Considering the localized phonon modes due to the impurity in a one-dimensional system, we have obtained the temporal evolution of the localization of photons, which depends on the photon–phonon coupling constant, as well as the hopping constant of photons. Numerical results show that photons move and localize at the impurity sites when the hopping constant is comparable to the photon–phonon coupling.

Optical near field dressed by localized and coherent phonons.

Exciton dynamics in molecular crystals from line shape analysis. Spectral moment analysis of the origin region of the 4000 Å transition of crystal anthracene

A canonical transformation which eliminates the trilinear exciton–phonon interaction and introduces new elementary excitations — “dressed” excitons — is proposed; it holds true both for the narrow and for broad exciton bands The energy spectrum of the dressed excitons is investigated in detail for a one-dimensional model of Frenkel excitons interacting with optical phonons



Es wird eine kanonische Transformation vorgeschlagen, die die trilineare Exziton–Phonon-wechselwirkung eliminiert und neue Elementaranregungen, „bekleidete” Exzitonen, einfuhrt Dies gilt sowohl fur schmale als auch fur breite Exzitonenbanden Das Energiespektrum der bekleideten Exzitonen wird ausfuhrlich fur ein eindimensionales Modell von Frenkel-Exzitonen, die mit optischen Phononen wechselwirken, untersucht

On the canonical transformation in the theory of exciton–phonon interaction

Temperature behavior of the integral intensity of exciton absorption

A joint effect of exciton–phonon and exciton–exciton interactions on optical properties of semiconductors is studied. In these substances the exciton density is shown to be a multivalued function of incident light intensity and the frequency and temperature conditions under which the optical bistability arises are specified. Investigation of nonlinear optical properties of semiconductors with account for the indirect phototransitions exhibits that both multistable optical states and the bistable ones distinguished by a complicated dynamics of the switching may be observed in such systems.



[Russian Text Ignored].

G. M. Pestryakov

Papers

On the canonical transformation in the theory of exciton–phonon interaction

Temperature behavior of the integral intensity of exciton absorption

Exciton–Phonon Mechanism of Optical Bistability

Nonlinearity of Absorption in an Exciton-Phonon System

Temperature Anomalies of Exciton Absorption in GeO2