SUPERPOSITION OF WAVES

Waves of different k vector, same frequency

Counter-propagating waves

Intersecting waves

Waves mixing (AOM)

Co-propagating, random phase

Waves of the same k vector, same frequency

Waves of the same k vector direction, different frequencies

Beat note

Creation of an arbitrary

Group velocity

Constructive and destructive Superposition is just like adding twovectors ,

Waves of the same k vector, same frequency

constructive destructive

Waves of the same k vector, same frequency Energy conservation

If the energy is lost by destructive interference, it has to reappear somewhere elseby constructive interference

and a complex transmission coefficient

Incident intensity

Energy conservation:

Reflected intensity

Transmitted intensity

A beam splitter is an element with a complex reflection coefficient

Waves of the same k vector, same frequency Energy conservation

If the energy is lost by destructive interference, it has to reappear somewhere elseby constructive interference

and a complex transmission coefficient

Energy conservation:

A beam splitter is an element with a complex reflection coefficient

Waves of the same k vector, same frequency Energy conservation

Mach Zehnder:

Michelson

Waves of the same k vector, same frequency Energy conservation

Antiresonant ring

Random and Coherent source

APPLICATIONS

Mach Zehnder: measurement of small absorption, index of refraction

Michelson Wavemeter

Antiresonant: extracting light from a cavity

SUPERPOSITION OF WAVES

Waves of (nearly) the same k vector, same frequency:Fresnel biprism

Given the angle, what is the fringe spacing?

How to determine the angle of the biprism?

P

S1

S2

SUPERPOSITION OF WAVES

Waves of (nearly) the same k vector, same frequency:Young’s double-slit experiment

Interference of two circular waves – Wavelength (decreasing bottom to top) and wave centers distance (increasing to the right)

Waves of different k vector, same frequency

SUPERPOSITION OF WAVES

Waves of different k vector, same frequency

Counter-propagating waves

Intersecting waves

Waves mixing (AOM)

Co-propagating, random phase

Waves of the same k vector, same frequency

Waves of the same k vector direction, different frequencies

Beat note

Creation of an arbitrary

Group velocity

Waves mixing: not necessarily optical wavesExample: AOM

FABRY-PEROT