London penetration depth
E48480
The London penetration depth is a characteristic length scale in superconductors that measures how far an external magnetic field can penetrate into the material before being exponentially screened.
All labels observed (1)
| Label | Occurrences |
|---|---|
| London penetration depth canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T380113 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: London penetration depth Context triple: [Meissner effect, relatedConcept, London penetration depth]
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A.
Silicon Fen
Silicon Fen is the high-tech business and research cluster around Cambridge, England, known for its concentration of technology, software, and biotech companies.
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B.
London, England
London, England is the capital and largest city of the United Kingdom, renowned as a global center for finance, culture, and politics.
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C.
Manchester city centre
Manchester city centre is the main commercial, retail, and cultural hub of Manchester, England, known for its shopping districts, nightlife, and historic architecture.
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D.
Gresham
Gresham is a suburban city in the Portland metropolitan area of northwestern Oregon, known for its residential communities and proximity to outdoor recreation in the Columbia River Gorge.
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E.
Chocolate City
Chocolate City is a popular nickname for Washington, D.C., highlighting its historically large and influential African American population and culture.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: London penetration depth Target entity description: The London penetration depth is a characteristic length scale in superconductors that measures how far an external magnetic field can penetrate into the material before being exponentially screened.
-
A.
Silicon Fen
Silicon Fen is the high-tech business and research cluster around Cambridge, England, known for its concentration of technology, software, and biotech companies.
-
B.
London, England
London, England is the capital and largest city of the United Kingdom, renowned as a global center for finance, culture, and politics.
-
C.
Manchester city centre
Manchester city centre is the main commercial, retail, and cultural hub of Manchester, England, known for its shopping districts, nightlife, and historic architecture.
-
D.
Gresham
Gresham is a suburban city in the Portland metropolitan area of northwestern Oregon, known for its residential communities and proximity to outdoor recreation in the Columbia River Gorge.
-
E.
Chocolate City
Chocolate City is a popular nickname for Washington, D.C., highlighting its historically large and influential African American population and culture.
- F. None of above. chosen
Statements (49)
| Predicate | Object |
|---|---|
| instanceOf |
characteristic length scale
ⓘ
physical quantity ⓘ superconductivity concept ⓘ |
| appearsIn | Ginzburg–Landau theory of superconductivity ⓘ |
| appliesTo | superconductor ⓘ |
| assumes | local electrodynamics in London theory ⓘ |
| canBeMeasuredBy |
magnetization measurements
ⓘ
microwave resonator techniques ⓘ muon spin rotation ⓘ optical reflectivity ⓘ tunnel diode resonator method ⓘ |
| characterizes | exponential decay of magnetic field ⓘ |
| definedAs | distance over which magnetic field decays by factor e in a superconductor ⓘ |
| dependsOn |
charge of Cooper pairs
ⓘ
effective mass of Cooper pairs ⓘ superfluid density ⓘ |
| describes | magnetic field penetration in superconductors ⓘ |
| divergesAt | critical temperature ⓘ |
| entersExpression | screening current density in superconductors ⓘ |
| fieldOfStudy |
condensed matter physics
ⓘ
low-temperature physics ⓘ |
| hasAlternativeSymbol | λ_L ⓘ |
| hasDimension | length ⓘ |
| hasSymbol | λ ⓘ |
| increasesWith | temperature ⓘ |
| isLargerFor | dirty or disordered superconductors ⓘ |
| isShorterThan | skin depth in normal metals at low frequencies ⓘ |
| isSmallerFor | materials with higher superfluid density ⓘ |
| measuredIn |
angstrom
ⓘ
meter ⓘ nanometer ⓘ |
| namedAfter |
Fritz London
ⓘ
Heinz London ⓘ |
| occursInEquation | B(x) = B(0) exp(-x / λ) ⓘ |
| partOfTheory | London equations ⓘ |
| relatedByFormula | λ^2 = m / (μ0 n_s q^2) in London theory ⓘ |
| relatedTo |
Meissner effect
ⓘ
coherence length ⓘ magnetic susceptibility of superconductors ⓘ superconducting energy gap via temperature dependence ⓘ |
| symbolUses |
m for effective mass in its formula
ⓘ
n_s for superfluid carrier density in its formula ⓘ q for carrier charge in its formula ⓘ μ0 for vacuum permeability in its formula ⓘ |
| temperatureDependent | true ⓘ |
| typicalMagnitude |
hundreds of nanometers for high-temperature superconductors
ⓘ
tens of nanometers for conventional superconductors ⓘ |
| usedIn | classification of type I and type II superconductors ⓘ |
| usedToDefine |
Ginzburg–Landau theory of superconductivity
ⓘ
surface form:
Ginzburg–Landau parameter
|
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: London penetration depth Description of subject: The London penetration depth is a characteristic length scale in superconductors that measures how far an external magnetic field can penetrate into the material before being exponentially screened.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.