Optical Excitations: Quantum Mechanics

Alan V. Durrant, Joy Manners, Paul M. Clark

The mechanism of optical echo (photon echo) formation in solid and gas media is described. The treatment is based on solutions of Schrodinger's equation for the time evolution of atomic amplitudes during an optical excitation pulse sequence, and should be accessible to non-specialists and to students studying undergraduate quantum mechanics. Atomic amplitude evolution diagrams are developed to facilitate the analysis of the echo mechanism and the derivation of the echo time and propagation direction.

Ángel S. Sanz, Salvador Miret-Artés

Tsafrir Armon, L. Frièdland

The interplay between classical and quantum-mechanical evolution in the optical centrifuge (OC) is discussed. The analysis is based on the quantum-mechanical formalism starting from either the ground state or a thermal ensemble. Two resonant mechanisms are identified, i.e., the classical autoresonance and the quantum-mechanical ladder climbing, yielding different dynamics and rotational excitation efficiencies. The rotating-wave approximation is used to analyze the two resonant regimes in the associated dimensionless two-parameter space and calculate the OC excitation efficiency. The results show good agreement between numerical simulations and theory and are relevant to existing experimental setups.

Miguel Orszag

Daniel F. Walls, Gerard J Milburn

David S. Bradshaw, Davıd L. Andrews

When fluorescence from electronically excited states follows the absorption of radiation, the emission spectrum is often a key to identification of the excited species. It now emerges that passing off-resonant laser light through such an electronically excited system may enhance or suppress the fluorescent emission. This report establishes the mechanism and theory for this optical control of spontaneous fluorescence, derived by quantum electrodynamical analysis. Experimental techniques to detect the enhanced signal are also proposed.