Echo-spectroscopy of nanocomposites

Abstract

Methods of characterization of nanocomposites consisting of semiconductor quantum dots incorporated into a transparent nonlinear dielectric matrix are elaborated. Spectral composition, observation time, and phase-matching conditions for echo-responses excited by two noncollinear pulses are analysed. More specifically, spectral and spatial features of echo signals caused by permanent dipole moments (PDMs) inherent to quantum dots and local field effects in them, as well as by the angular distribution function of the PDM orientations and spatial dispersion of transition dipole moments, are considered.

Unified Model for a Nonlinear Pulse Propagation in Composites and Optimization of THz Generation

“…We note, however, that this conclusion is of limited generality; for other parameters of the medium excitons can provide the key mechanism of THz generation (see e.g. [45,46] and references therein).…”

Peculiarities of Rabi oscillations and free induction decay in two-component nuclear spin systems with Ising nuclei interactions

“…It can be seen from ( 10) that the third and fourth terms lead to static and time-dependent (dynamic) energy level shifts of the 1st subsystem, respectively [11,25,35,39]. Note that the Hamiltonian (10) is similar to the one describing a two-level system under parametric excitation [40] for which the fourth term is responsible.…”