The aim of the course is to describe the principles of lasers and laser action. The course covers interactions of atoms and molecules with light (absorption, emission and dispersion) and includes concepts such as Doppler, collision, and natural lifetime broadening, population inversion, and optical pumping. The principles of laser resonators and laser action (gain, threshold, power) are discussed. The course will treat some common types of laser in more detail, including continuous-wave (cw) and pulsed, gas and solid-state lasers and at the end, some laser applications will be discussed.

Learning Outcomes: At the end of this course, students should be able to:

  1. Explain the operational principles and construction of lasers
  2. Describe optical components that can be used to tailor the properties of the laser
  3. Distinguish between the different optical cavities/resonators.
  4. Describe the conditions of producing a laser beam.
  5. Describe how pulsed laser beams can be obtained from a laser cavity.
  6. Understand the laser applications in daily life.


  1. Introduction to Lasers
  2. Properties of laser beam
  3. Electromagnetic waves and photons
  4. Energy levels, Transition and spectral lines, The metastable level
  5. Spontaneous and Stimulated emission, Stimulated Absorption
  6. Line shape function
  7. Black-Body Radiation
  8. Relation between Einstein A and B Coefficients
  9. Conditions for large stimulated emissions
  10. Gain coefficient and threshold Gain coefficient
  11. Line-broadening mechanism
  12. Population inversion
  13. The three and four-level system
  14. Rate equations
  15. Optical resonators
  16. Conditions for steady state oscillation in a two mirror Resonator
  17. Cavity resonance frequencies
  18. Longitudinal and Transverse modes in a cavity
  19. Pumping Process, Pulsed vs Continuous emission
  20. Threshold condition and output power
  21. Optimum output coupling
  22. Laser tuning
  23. Oscillation and pulsations in lasers
  24. Q-Switching and mode-locking methods
  25. Phase velocity and Group Velocity
  26. Dispersion and Pulse Width
  27. Non-linear crystals
  28. Solid state lasers: Ruby Laser, Nd:YAG and Nd:Glass lasers
  29. Semiconductor lasers: Homojunction lasers, Double Hetrostructure lasers
  30. Gass Lasers: Helium Neon laser, CO2 laser, Nitrogen laser and Excimer laser
  31. Free-Electro and X-ray lasers
  32. Laser Applications.

Recommended Books

  1. Laser Fundamentals by W. T. Silfvast, Cambridge University press, (2003).
  2. Understanding lasers b y J. Hecht, Howard W. Sams & Company, USA (1988).
  3. Lasers by P. W. Milonni and J. Eberly, Wiley, New York. (2010).
  4. An Introduction to Lasers by M. N. Avadhanulu, S. Chand & company (2001).

Suggested Books

  1. Principles of lasers by O. Svelto, Plenum press new York & London (1992).
  2. Lasers by A.E. SiegmanUniversity, Science Books Mill Valley, C. A. (1986).
  3. Laser Theory by H. Haken, Springer, Berlin (2003).
  4. Lasers, Principles and Applications by J. Wilson and J. F. B. Hawkes, Prentice Hall, New York, (1988).
  5. Lasers and Electro-Optics: Fundamental and Engineering by Christopher C. Davis, Cambridge University press, (1996).


  • Sessional: 20 (Presentation / Assignment 10, Attendance 05, Quiz 05)
  • Mid-Term Exam: 30
  • Final-Term Exam: 50

Time of Class Meeting

Monday to Wednesday                 9:30 am to 10:30 am

Key Dates

Commencement of Classes                                                   January 13, 2020

Mid Term Examination                                                            March 16 to March 23, 2020

Final Term Examination                                                          May 11-15, 2020

Declaration of Result                                                              May 22, 2020

Course Material