I= QUANTUM THEORY OF TWO-PHOTON MICROMASER AND LASER
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Title of Thesis
QUANTUM THEORY OF TWO-PHOTON MICROMASER AND LASER

Author(s)
IMRANA ASHRAF
Institute/University/Department Details
Department of Physics/ Quaid-i-Azam University, Islamabad
Session
1989
Subject
Physics
Number of Pages
120
Keywords (Extracted from title, table of contents and abstract of thesis)
quantum theory, two-photon micromaser, laser linewidth, two €“photon laser, multi-level micromaser

Abstract
In this dissertation, we study the quantum theory of two-photon micromaser and laser. To begin with, we study the photon statistics of the two-photon micromaser by considering the interaction of a quantized single-mode field with an effective two-level atom through intermediate states. We present an exact solution for the photon distribution function and study the behaviour of mean photon number and photon number fluctuations. A periodic "collapse" and "revival" type behaviour is predicted. We find that the photon number fluctuations exhibits a periodic sub-Poissonian behaviour with respect to the interaction time. We then discuss the photon statistics of two-photon laser and derive an exact expression for photon distribution function. We find that photon distribution function for two-photon laser is wider than the Poisson distribution function. We also calculate the natural line-width of a two-level two-photon laser by using a Fokker-Planck approach. It is shown that, apart from a constant, the gain contribution to the laser linewidth is equal to the two-photon gain parameter and is independent of the mean number of photons in the field. Finally, we study the two-photon transitions in multi-level atomic system. In this case first we discuss the photon statistics of three-level two-photon micromaser and laser. Then we consider the two-photon transition in four-level atomic system by considering dye laser as an example.

Download Full Thesis
1055.27 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
75.39 KB
2 1 Introduction
61.75 KB
  1.1 Two-Photon Micromaser 1
  1.2 Two €“Photon Laser 4
  1.3 Two-Photon Multi-Level Micromaser And Laser 5
3 2 Photon Statistics Of A Two-Photon Micromaser
252.62 KB
  2.1 Introduction 9
  2.2 Quantum Theory Of A Single-Photon Micromaser 10
  2.3 Probability Amplitudes For The Two-Photon Micromaser 23
  2.4 Photon Statistics Of A Two Photon Micromaser 29
  2.5 Linewidth Of A Two-Photon Micromaser 40
  2.6 Discussion 41
4 3 Quantum Theory Of A Two-Level Two-Photon Laser
192.49 KB
  3.1 Introduction 42
  3.2 Review Of Scully-Lamb Theory Of Laser 43
  3.3 Equation Of Motion For Reduced Density Matrix For The Field In The Two- Photon Laser 54
  3.4 Natural Linewidth Of Two-Photon Laser 59
  3.5 Discussion 66
5 4 Two-Photon Transitions In Multi-Level Atoms
459.92 KB
  4.1 Introduction 69
  4.2 Two-Photon Transitions In Three-Level Atom 70
  4.3 Two-Photon Transitions In Four-Level System 89
  4.4 Discussion 105
6 5 References 107
166.25 KB
  5.1 Appendix A 111
  5.2 Appendix B 116