Semiconductor Plasmonic Propagation Length Calculator
Extract actual intensity 1/e plasmonic propagation length from log-intensity spatial fit, not field-amplitude factor-of-two length, or supplied loss times distance.
Description
An intensity decay fit defines a plasmonic propagation length at the 1/e intensity level.
An intensity decay fit defines a plasmonic propagation length at the 1/e intensity level.1
Using intensity rather than field amplitude fixes the factor-of-two convention.
When to use Semiconductor Plasmonic Propagation Length Calculator
Use this tool when you need to fit an apparent exponential decay length or time. Prepare measured device or specimen records under independently matched branch, temperature, frame, and unit conventions.
How to use Semiconductor Plasmonic Propagation Length Calculator and understand its results
- Prepare measured device or specimen records under independently matched branch, temperature, frame, and unit conventions.
- Enter observedPlasmonPositionsM, observedPlasmonIntensity, following the field table and rules below, then run the tool.
- Read fittedIntensityPropagationLengthM, fitRSquared. Use the output meanings below to interpret units, signs, flags, and any nested result fields.
- Correct reported input issues and run again. For a successful result, check the stated evidence coverage and assumptions before using it in your review.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedPlasmonPositionsM | Observed plasmon positions m | list of number | Required |
| observedPlasmonIntensity | Observed plasmon intensity | list of number | Required |
Use at least two aligned coordinates and strictly positive signal values with nonzero coordinate variance. Fit the natural logarithm of signal against coordinate by ordinary least squares with a free intercept. Require a negative fitted slope; nondecaying fitted traces are rejected. Return the negative reciprocal of slope and the log-domain R². Coordinates need not be sorted, and an individually increasing sample can be accepted if the fitted trend is negative.
ln(signal)=a+b×coordinate; decayLengthOrTime=−1/b, b<0 Symbols follow the input and output meanings and the calculation rules above.
The result is a length in metres. Coordinate values are only required to be finite with distinct predictors; nonnegativity and individual monotonic decay are not separately enforced.
| Output field | Meaning | Value type |
|---|---|---|
| fittedIntensityPropagationLengthM | Fitted intensity propagation length m | number |
| fitRSquared | Fit R² | number |
{
"input": {
"observedPlasmonPositionsM": [
0,
1,
2
],
"observedPlasmonIntensity": [
4,
2,
1
]
},
"output": {
"fittedIntensityPropagationLengthM": 1.4426950408889634,
"fitRSquared": 1
}
}Limitations and assumptions
An exponential model and selected measurement branch must be justified independently. R² summarizes a log-domain fit; it is not a confidence interval, full physical model, or device readiness check.
Missing required fields, unknown fields, wrong types, and violated calculation rules are input issues. Numeric values must be finite; nonfinite results are rejected. Evidence arrays must be dense, with no missing cells. Numeric observation lists allow at most 10,000 entries, subject to any smaller bounds stated above.
Alternative or Complementary methods
For a related review, use Semiconductor Plasmonic Waveguide Confinement Factor Calculator: Modal confinement is an energy-weighted regional fraction rather than a geometric volume fraction. In a dispersive plasmonic system the energy-density definition must be established independently. For a complementary step, use Semiconductor Silicon Photonics Waveguide Bending Loss Calculator: Excess bend loss compares a bent guide with a matched straight reference. Dividing the logarithmic power difference by the observed bend count yields a per-bend observation.
References
Similar or alternative tools
- Semiconductor Plasmonic Waveguide Confinement Factor Calculator
Modal confinement is an energy-weighted regional fraction rather than a geometric volume fraction. In a dispersive plasmonic system the energy-density definition must be established independently.
- Semiconductor Silicon Photonics Waveguide Bending Loss Calculator
Excess bend loss compares a bent guide with a matched straight reference. Dividing the logarithmic power difference by the observed bend count yields a per-bend observation.