BBO Entanglement Setup Check
Estimate a two-basis BBO entanglement CHSH value from measured visibilities.
Description
A two-basis visibility model estimates CHSH S from mean visibility.
A two-basis visibility model estimates CHSH S from mean visibility. It is an estimate under the chosen scaling relation, not a direct four-correlation calculation.1
Estimate a two-basis BBO entanglement CHSH value from measured visibilities.
When to use BBO Entanglement Setup Check
Use this tool to estimate a two-basis BBO entanglement CHSH value from measured visibilities.
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 BBO Entanglement Setup Check 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 rectilinearVisibility, diagonalVisibility, violationThreshold using the field table and calculation rules, then run the tool.
- Read meanVisibility, estimatedChshS, exceedsThreshold. 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 |
|---|---|---|---|
| rectilinearVisibility | Rectilinear-basis visibility | number; minimum: 0; maximum: 1 | Required |
| diagonalVisibility | Diagonal-basis visibility | number; minimum: 0; maximum: 1 | Required |
| violationThreshold | CHSH violation threshold | number; minimum: 0 | Required |
Enter visibilities 0–1 and nonnegative threshold. Return mean, S estimate and strict threshold-exceedance flag.
mean=(Vrect+Vdiag)/2; estimatedS=2sqrt(2)mean Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| meanVisibility | Mean visibility | number; minimum: 0; maximum: 1 |
| estimatedChshS | Estimated CHSH S | number; minimum: 0 |
| exceedsThreshold | Exceeds threshold | boolean |
{
"input": {
"rectilinearVisibility": 0.9,
"diagonalVisibility": 0.8,
"violationThreshold": 2
},
"output": {
"meanVisibility": 0.8500000000000001,
"estimatedChshS": 2.404163056034262,
"exceedsThreshold": true
}
}Limitations and assumptions
No uncertainty, measurement settings, loophole closure or entanglement certification is evaluated.
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. A successfully returned false flag is an evaluated outcome; its meaning is explained above.
Alternative or Complementary methods
Use BB84 Sift Error Analysis: Sift aligned BB84 records and calculate the sifted-key error rate. For a complementary task, use CHSH Violation: Calculate CHSH S from four measured correlations.
References
-
BBO Entanglement Setup Check — tool.io
Similar or alternative tools
- BB84 Sift Error Analysis
Sift aligned BB84 records and calculate the sifted-key error rate.
- CHSH Violation
Calculate CHSH S from four measured correlations.