NFYA05020U Optical Physics and Lasers

Skills
Upon completion of the course the student should be able to:

• Derive the Lorentzian lineshape function and explain the origin of the Doppler spectral width.
• Derive expressions for the refractive index and absorption and gain coefficients of atomic medium.
• understand the origin of laser gain, losses and the feedback mechanism and the laser threshold.
• explain photon- and population rate equations for three- and four-level lasers.
• explain the difference between saturated gain and small signal gain of a laser.
• discuss the nature of the laser linewidth and methods of obtaining single mode operation.
• explain the origin of the theoretical lower limit for laser bandwidth (Schawlow-Townes limit). understand the principles of Q-switch lasers and mode-locked lasers.
• calculate Gaussian beam propagation using ABCD matrix formalism.
• understand the quantum theory of a two-level atom interacting with light including Rabi oscillations and Pi pulses.
• understand the basics of coherent effects in laser-atom interactions, such as electromagnetically induced transparency.
• explain the theory of nonlinear optical processes driven by laser light including second harmonic generation.

Knowledge

• The basics of interaction of light with matter including absorption, stimulated and spontaneous emission of light
• Lorentz model of atom-light interaction
• The theory of spectral line shapes
• Pulsed lasers
• Optical resonators
• Specific modern lasers
• Atomic density matrix and Bloch equations
• Quantum effects such as Rabi oscillations and electromagnetically induced transparency

Competences
The course forms the basis for future studies of coherent and quantum effects within atomic and optical domains including quantum optics, quantum solid state photonics and experimental realizations of quantum information processing. The course should be also useful for students of other disciplines who expect to use lasers in one way or another.