L9 Flashcards
Temporal Coherence
Definition: Measure of the correlation between the phases of a wave at different points along its propagation direction.
Wiener-Khinchin Theorem
Theorem: The autocorrelation function of a signal is the Fourier transform of its power spectral density.
Fabry-Perot Interferometer
What does it consist of and what can one measure using it?
- Consists of two parallel mirrors.
- Used to measure the spectral lines of light with high resolution.
Matrix Method
- Used to analyse multiple surface reflections in an interferometer.
- Uses propagation and scattering matrices.
Fabry-Perot Transmission
What is it described by and what does it depend on?
- Described by the Airy formula.
- Depends on the phase difference between successive reflections.
Finesse
- A measure of the spectral resolution of the Fabry-Perot interferometer.
- High finesse means narrow spectral lines.
Free Spectral Range
The frequency interval between successive transmission peaks of the interferometer.
Spectral Width
- The width of the transmission peaks.
- Related to the finesse of the cavity.
Scattering Matrix
Describes how an electromagnetic wave propagates through an interface between two media.
Fresnel Coefficients
Describe the reflection and transmission of light when incident on an interface between two different media.
Optical Filters
Application: Fabry-Perot cavities are used to create optical filters with high resolution.
Laser Cavities
Application: Fabry-Perot interferometers are used in laser cavities to select specific wavelengths of light.
