

Title of Thesis
EFFECT OF THE DYNAMIC SHIFT ON THE QUANTUM ELECTRODYNAMICS OF AN ATOM MAKING TWOPHOTONS IN AN IDEAL CAVITY 
Author(s)
TAHIRA NASREEN 
Institute/University/Department Details
Department of Physics/ QuaideAzam University Islamabad, Pakistan 
Session
1992 
Subject
Physics 
Number of Pages
192 
Keywords (Extracted from title, table of contents and abstract of thesis)
dynamic shift, quantum electrodynamics, ideal cavity, dynamical stark shift, photon transitions, quantized radiation field, nondegenerate twophoton jaynescummings model, ntpjcm, twophoton processes, twophoton effective hamiltonian, emission spectra, cavity field spectrum, field wave function 
Abstract In this thesis, we investigate the effect of the dynamical Stark shift on the quantum electrodynamics of an atom undergoing twophoton transitions, interacting with a quantized radiation field in an ideal cavity. To begin with, we discuss the dynamics of the electromagnetic field and the atom in the presence of the Stark shift. We derive closed expressions for the secondorder coherence function, quadrature variances, atomic population inversion and dipole squeezing under the approximation of a large initial photon number and coherent or squeezed field input. We show that for an atom initially in the ground state, the inclusion of Stark shift reduces the field squeezing as well as the antibunching. Both the population inversion and the dipole squeezing exhibit phase sensitivity in the presence of Stark shift and for a particular choice of the relative phase of the two atomic levels "trapping" occurs in a twolevel atom and the dipole is modified in such a way that it is permanently squeezed. We then discuss the effect of the stark shift on the emission spectrum of an atom and the cavity field spectrum. The inclusion of Stark shift results in asymmetric vacuum field Rabi splitting. We also study the dynamics of the combined atomfield wave function in the presence of the Stark shift and show that both the electromagnetic field and the atom periodically evolve to pure states which are radically different from those in the absence of the Stark shift. Finally, we study the nondegenerate twophoton JaynesCummings model (NTPJCM) in the presence of the Stark shift and show that the dynamics of the NTPJCM in the presence of Stark shift is qualitatively different from the case of the absence of the Stark shift and radically different from the case of degenerate twophoton JCM in the presence of Stark shift.






S. No. 
Chapter 
Title of the Chapters 
Page 
Size (KB) 





1 
0 
Contents 

178.43 KB 





2 
1 
Introduction 

2448.71 KB 

1.1 
Twophoton Processes 
1 

1.2 
Degenerate TwoPhoton Effective Hamiltonian in the Presence of Stark Shift 
3 

1.3 
Nondegenerate TwoPhoton Effective Hamiltonian in the Presence of the Stark Shift 
6 

1.4 
Organization of the Thesis 
9 





3 
2 
Dynamics Of The Field 

402.35 KB 

2.1 
Introduction 
13 

2.2 
TwoPhoton Jaynes Cummings Model in the Presence of Stark Shift 
15 

2.3 
Evolution of the Density Matrix 
21 

2.4 
SecondOrder Coherence Function 
27 

2.5 
Squeezing of the Radiation Field 
42 

2.6 
Conclusions 
55 





4 
3 
Dynamics Of The Atom 

428.98 KB 

3.1 
Introduction 
57 

3.2 
Expectation Values of the Atomic Operators 
61 

3.3 
Population Inversion 
68 

3.4 
Atomic Dipole Squeezing 
78 

3.5 
Conclusions 
92 





5 
4 
Spectral Properties Of The Atom And The Field 

339.89 KB 

4.1 
Introduction 
94 

4.2 
The Emission Spectra of the Atom 
95 

4.3 
Cavity Field Spectrum 
114 

4.4 
Conclusions 
128 





6 
5 
Evolution Of Wave Function 

276.45 KB 

5.1 
Introduction 
130 

5.2 
Coupled AtomField Wave Function 
132 

5.3 
Evolution of the Wave Function In the absence of Stark Shift 
134 

5.4 
Evaluation of the Wave Function in the presence of Stark Shift 
147 

5.5 
Conclusions 
156 





7 
6 
Dynamics Of Nondegenerate TwoPhoton JCM 

327.61 KB 

6.1 
Introduction 
158 

6.2 
Model and System of Equations 
160 

6.3 
Atomic Dipole Squeezing 
166 

6.4 
The Emission Spectra of the Atom 
173 

6.5 
Conclusions 
184 

6.6 
Refrences 
185 





