Decoy-State Intensity Score
Score supplied signal and decoy intensities from observed gains; this is not a security proof.
Description
Signal/decoy intensity scoring combines supplied mean photon numbers with observed gains.
Signal/decoy intensity scoring combines supplied mean photon numbers with observed gains. The result is a heuristic comparison rather than a key-rate bound.1
Score supplied signal and decoy intensities from observed gains; this is not a security proof.
When to use Decoy-State Intensity Score
Use this tool to score supplied signal and decoy intensities from observed gains; this is not a security proof.
Prepare the optical measurements, geometry, fitted coefficients or caller-selected thresholds requested. Confirm wavelength, radius/diameter, pulse-width, angle and unit conventions before running the calculation.
How to use Decoy-State Intensity Score and understand its results
- Prepare the optical measurements, geometry, fitted coefficients or caller-selected thresholds requested. Confirm wavelength, radius/diameter, pulse-width, angle and unit conventions before running the calculation.
- Enter signalMeanPhotons, signalGain, decoyMeanPhotons, decoyGain, vacuumGain using the field table and calculation rules, then run the tool.
- Read signalDetectionScore, decoyDetectionScore, signalToDecoyScoreRatio. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| signalMeanPhotons | Signal mean photon number | number; minimum: 0 | Required |
| signalGain | Signal detection gain | number; minimum: 0 | Required |
| decoyMeanPhotons | Decoy mean photon number | number; minimum: 0 | Required |
| decoyGain | Decoy detection gain | number; minimum: 0 | Required |
| vacuumGain | Vacuum detection gain | number; minimum: 0 | Required |
Enter nonnegative values. Return both scores and signal/decoy ratio, using zero as a placeholder when decoy score is zero.
signalScore=µsignal×signalGain; decoyScore=µdecoy×max(0,decoyGain−vacuumGain) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| signalDetectionScore | Signal intensity score | number; minimum: 0 |
| decoyDetectionScore | Decoy intensity score | number; minimum: 0 |
| signalToDecoyScoreRatio | Signal-to-decoy score ratio | number; minimum: 0 |
{
"input": {
"signalMeanPhotons": 0.5,
"signalGain": 0.1,
"decoyMeanPhotons": 0.1,
"decoyGain": 0.05,
"vacuumGain": 0.01
},
"output": {
"signalDetectionScore": 0.05,
"decoyDetectionScore": 0.004,
"signalToDecoyScoreRatio": 12.5
}
}Limitations and assumptions
Gains are not capped at one. No photon-number yield estimation, QBER, finite-key analysis or security proof is supplied.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Twin-Field PLOB Comparison: Compare an achieved twin-field secret-bit rate with the repeaterless PLOB bound. For a complementary task, use Repeater-Link Success: Estimate independent quantum-repeater chain success across repeated attempts.
References
-
Decoy-State Intensity Score — tool.io
Similar or alternative tools
- Twin-Field PLOB Comparison
Compare an achieved twin-field secret-bit rate with the repeaterless PLOB bound.
- Repeater-Link Success
Estimate independent quantum-repeater chain success across repeated attempts.