Quantized Energy Exchanges

G. Drobný, Igor Jex

We analyze the collapse and revival phenomenon in the energy exchange of two field modes initially prepared in a Fock state, as well as their coherent superposition in the process of k-photon down-conversion with quantized pump. The influence of the presence of a Kerr-like medium is discussed.

Dhruba J. Biswas

Paul Peter Urone, Roger A. Hinrichs

Georg Sulyok, Johann Summhammer, H. Rauch

We investigate the scattering of a quantum-mechanical particle on an oscillating rectangular potential barrier. In the first step, we show the calculation for a classical potential revealing coherent, quantized energy exchange between the particle and potential, respectively, the likewise classical field that generates the latter. In order to explore the quantized energy transfer in more detail, the transition to a quantum field is performed and the Schr\"odinger equation for the composite quantum system consisting of particle and field is solved analytically as well. The result allows a physically very intuitive explanation of the underlying energy exchange processes and explicitly displays the occurring entanglement between particle and field due to their interaction, thus offering the possibility to use this combined system for quantum information experiments. Depending on the initial field state, incoherent or coherent energy exchange is observed. In the limit of high mean photon numbers the classical results can be fully retrieved.

S. T. Chui

The many-particle exchange integral for a class of correlated Gaussian wave functions for the fractionally quantized Hall effect are discussed. When the correlation is of a long-range nature, the evaluation of this exchange can be cast into languages involving the study of the energies and fluctuations of grain boundaries in two dimensions. For a class of trial wave functions studied recently by Chui, Ma, and Hakim, exchanges involving a large number of particles are significant in that, for a loop that consists of two long parallel boundaries, the overlap integral actually increases as the number of particles involved in the exchange is increased. The question of a collection of boundaries is discussed. We find that there is a repulsion between the boundaries of a range proportional to the size of the boundary.