Phase noise washes out fringes
Adjust the controls, inspect the calculated response and use the reading links to place the model in its physical context.
Interactive model: Phase noise washes out fringes. Enable JavaScript to adjust its controls.
V = exp(−σφ²/2); P = [1 + V cos φ]/2
Equal path populations and independent zero-mean Gaussian phase fluctuations averaged over many runs. This models the observed reduced fringe contrast; it does not identify the underlying cause of the noise.
What this model assumes
Equal path populations and independent zero-mean Gaussian phase fluctuations averaged over many runs. This models the observed reduced fringe contrast; it does not identify the underlying cause of the noise.
How to explore it
Begin with the default values. Change one control at a time and watch both the graph and the readouts. Then reset the model and change another parameter. This isolates which input produces the effect you are seeing.
The plotted values are generated from the displayed equation. Downloading the calculated data lets you inspect the numerical series or compare it with a calculation of your own. The data are synthetic model outputs, not observations from an apparatus.
Before carrying a prediction into an experiment, match the model’s assumptions to the actual system: the relevant degrees of freedom, boundary conditions, noise, losses and measurement convention. The linked articles explain which comparison is physically meaningful.
Calculated model curves. Equal path populations and independent zero-mean Gaussian phase fluctuations averaged over many runs. This models the observed reduced fringe contrast; it does not identify the underlying cause of the noise. Default control values are used in this fixed figure.
Download SVG ↓Phase scrambling and dephasing
Losing a pattern without losing all its energy
Which phase relationships must change for interference to wash out?
The phase that matters is relative
Why can a global phase change leave every observable unchanged?
A changed phase can still be fully controlled
How is known phase modulation different from random dephasing?
When averaging erases fringes
Can individual runs retain interference while their average looks flat?
Fast and slow noise affect coherence differently
How does a noise spectrum influence an interference measurement?
Recovering coherence lost to a known spread
What does an echo recover, and what remains irreversible?
Phase loss through correlations with an environment
How does entanglement differ from classical uncertainty about a phase?
A scrambled wavefront can create structured speckle
Why does apparent disorder still contain interference information?
Quantifying visibility and coherence time
Which measurements distinguish phase noise from intensity noise?
What phase scrambling does not establish
Why does lost interference alone not identify a unique collapse mechanism?