Comparison of Harmonic Oscillator Model in Classical and Quantum Theories of Light-Matter Interaction

Abstract

A brief review of the classical and quantum description of the interaction of electromagnetic radiation with matter based on the model of a harmonic oscillator is presented. This review includes the generalized Bohr correspondence principle, the excitation of a quantum oscillator by electromagnetic pulses including saturation effect, the harmonic limit of the Bloch equations, and a phenomenological account of the damping of the quantum oscillator. In all cases, at the mathematical level, the relationship between the classical and quantum descriptions of the electromagnetic interaction is established and the conditions for such compliance are identified.

Keywords

• classical and quantum harmonic oscillators
• photoexcitation
• Bohr correspondence principle
• Schwinger formula
• saturation effect
• Bloch equations