Atom-field interaction

More specifically, the unique modal field profile and characteristics of the CBNL structure are advantageous for biochemical sensing applications, but also for surface emitting lasers and for studies involving strong atom-field interactions such as nonlinear optics and cavity QED. 

The linear response function [3], R(r, r ) = (hp(r)/hv(r ))N, is used to study the effect of varying v(r) at constant N. If the system is acted upon by a weak electric field, polarizability (a) may be used as a measure of the corresponding response. A minimum polarizability principle [17] may be stated as, the natural direction of evolution of any system is towards a state of minimum polarizability. Another important principle is that of maximum entropy [18] which states that, the most probable distribution is associated with the maximum value of the Shannon entropy of the information theory. Attempts have been made to provide formal proofs of these principles [19-21], The application of these concepts and related principles vis-a-vis their validity has been studied in the contexts of molecular vibrations and internal rotations [22], chemical reactions [23], hydrogen bonded complexes [24], electronic excitations [25], ion-atom collision [26], atom-field interaction [27], chaotic ionization [28], conservation of orbital symmetry [29], atomic shell structure [30], solvent effects [31], confined systems [32], electric field effects [33], and toxicity [34], In the present chapter, will restrict ourselves to mostly the work done by us. For an elegant review which showcases the contributions from active researchers in the field, see [4], Atomic units are used throughout this chapter unless otherwise specified. 

G. Compagno, R. Passante, and F. Persico, Atom-Field Interactions and Dressed Atoms, Cambridge University Press, Cambridge, England, 1995. 

Since the atom-field interaction in the Fabry-Perot resonator is allowed for the two electric dipole transitions... 

Exact and Approximate Rate Equations in Atom-Field Interactions, S. Swain Atoms in Cavitites and Traps, H. Wahher Some Recent Advances in Electron-Impact Excitation of n = 3 States of Atomic Hydrogen and Helium, J. F. Williams and J. B. Hbng... 

Choice of the atom-field interaction operator. Formulation in terms of the full multipolar interaction... 

The review covers, apart from the methodology of solving the TDSE, the theory for the solution of the MEP in two broad subjects of modern research One which refers to isolated discrete and resonance states, and one which refers to the series of states just below and just above the fragmentation threshold. Thus, it is also concerned with the theory of the quantum defect and of related issues. The applications which are mentioned or are discussed briefly, involve either the ab initio computation of the time-resolved decay of autoionizing states, or, especially, prototypical TDMEPs of absorption of one or of many photons by atoms, by negative ions and by diatomics. In the latter case, we demonstrate how the multipolar interaction expressing the full atom-field interaction, (and not just the electric dipole approximation), can be incorporated into a practical computational methodology. 

Third, the choice of the form of the atom-field interaction operator must be correct and appropriate for the TDMEPs under investigation. This is crucial not only for the accuracy of the computation of h (f) and (f) but also for ensuring that (f) and bE t) dE indeed represent the time-dependent occupation probabilities that correspond to the stationary states of interest labeled by (discrete states) or by (scattering states). 

In the general area of atom-field interactions, when these are treated either semiclassically (the field is classical) or in terms of quantum electrodynamics, this subject has given rise to many discussions, expression of different... 

Another important electronic structure principle is the maximum hardness principle " (MHP) which may be stated as, There seems to be a rule of nature that molecules arrange themselves to be as hard as possible . Numerical verification of this principle has been made in several physico-chemical problems such as molecular vibrations , internal rotations , chemical reactions" , isomer stability , pericyclic reactions and Woodward-Hoffmann rules , stability of magic clusters , stability of super atoms ", atomic shell structure" , aromaticity , electronic excitations , chaotic ionization, time-dependent problems like ion-atom collision and atom-field interaction " etc. 

In terms of these functions, the Hamiltonian for the atom-field interaction is... 

N. Lu and S. Y. Zhu. Quantum theory of two-photon correlated-spontaneous-emission lasers Exact atom-field interaction Hamiltonian approach. Physical Revew A 1989 Nov 15 40(10) 5735-5752. 

But the most important goal of molecular quantum dynamics is probably to describe, understand, and conttol the elementary chemical processes at the most fundamental level, and it is the aim of the present book to provide some illustrations. This can be achieved by transferring all the methodology developed in quantum physics to the realm of molecular problems. In particular, the concepts of eigenstates, wavepackets, or even dressed states (dressed by an external field) used in quantum optics to describe atom-field interactions [174,175] can be used to describe chemical phenomena. Such an approach can lead to new insights into the interpretation of chemical processes not available with a pure static picture or a classical or even a semi-classical picture of the motion of the nuclei (at least not directly in the latter case). 

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