Composite fermion
E400608
A composite fermion is a quasiparticle formed by an electron bound to an even number of magnetic flux quanta, playing a key role in explaining the fractional quantum Hall effect.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Composite fermion canonical | 1 |
| Composite fermion theory | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T3921358 — 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: Composite fermion Context triple: [Fermion, isClassifiedAs, Composite fermion]
-
A.
Fermion
A fermion is a fundamental particle or composite particle that follows Fermi–Dirac statistics and the Pauli exclusion principle, forming the basic building blocks of matter such as electrons, protons, and neutrons.
-
B.
Fermi gas
A Fermi gas is a quantum many-particle system composed of fermions that obey Fermi–Dirac statistics, often used to model electrons in metals, neutrons in neutron stars, and ultracold atomic gases.
-
C.
Cooper pair
A Cooper pair is a bound state of two electrons (or other fermions) that move together in a correlated way, enabling superconductivity by forming a collective quantum state with zero electrical resistance.
-
D.
Fermi liquid theory
Fermi liquid theory is a framework in condensed matter physics that describes how interacting fermions in a metal behave like long-lived quasiparticles with properties similar to those of a non-interacting Fermi gas.
-
E.
Wigner crystal
A Wigner crystal is an ordered lattice of electrons that forms in low-density systems when their mutual Coulomb repulsion dominates over kinetic energy, leading to a crystalline arrangement of charge.
- 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: Composite fermion Target entity description: A composite fermion is a quasiparticle formed by an electron bound to an even number of magnetic flux quanta, playing a key role in explaining the fractional quantum Hall effect.
-
A.
Fermion
A fermion is a fundamental particle or composite particle that follows Fermi–Dirac statistics and the Pauli exclusion principle, forming the basic building blocks of matter such as electrons, protons, and neutrons.
-
B.
Fermi gas
A Fermi gas is a quantum many-particle system composed of fermions that obey Fermi–Dirac statistics, often used to model electrons in metals, neutrons in neutron stars, and ultracold atomic gases.
-
C.
Cooper pair
A Cooper pair is a bound state of two electrons (or other fermions) that move together in a correlated way, enabling superconductivity by forming a collective quantum state with zero electrical resistance.
-
D.
Fermi liquid theory
Fermi liquid theory is a framework in condensed matter physics that describes how interacting fermions in a metal behave like long-lived quasiparticles with properties similar to those of a non-interacting Fermi gas.
-
E.
Wigner crystal
A Wigner crystal is an ordered lattice of electrons that forms in low-density systems when their mutual Coulomb repulsion dominates over kinetic energy, leading to a crystalline arrangement of charge.
- F. None of above. chosen
Statements (46)
| Predicate | Object |
|---|---|
| instanceOf |
Emergent particle
ⓘ
Quasiparticle ⓘ |
| associatedWith |
Chern–Simons theory
ⓘ
surface form:
Chern–Simons gauge field
Flux attachment transformation ⓘ |
| composedOf |
Electron
ⓘ
Even number of magnetic flux quanta ⓘ |
| effectiveDescriptionOf | Strongly correlated electrons in high magnetic fields ⓘ |
| emergesAt |
Landau level filling factor ν = 1/2
ⓘ
Other even-denominator effective fields ⓘ |
| emergesIn |
quantum Hall effect
ⓘ
surface form:
Fractional quantum Hall regime
|
| explains |
Odd-denominator filling fractions
ⓘ
Sequence of fractional quantum Hall plateaus ⓘ |
| formedIn |
Strong perpendicular magnetic field
ⓘ
Two-dimensional electron gas ⓘ |
| hasEffectiveFillingFactor | p (integer) ⓘ |
| hasElectricCharge | Electron charge ⓘ |
| hasFillingFactorMapping | ν = p/(2p±1) ⓘ |
| hasProperty |
Can form Fermi sea at half-filled Landau level
ⓘ
Can form compressible metallic-like states ⓘ Can form incompressible quantum liquids ⓘ Charge transport carrier in fractional quantum Hall states ⓘ Effective mass different from bare electron mass ⓘ Electron bound to even number of flux quanta ⓘ Emergent from electron–electron interactions ⓘ Emergent gauge field coupling ⓘ Forms Landau-like levels (Λ levels) ⓘ Maps fractional quantum Hall states to integer quantum Hall states of composite fermions ⓘ Quasiparticle lifetime determined by interactions and disorder ⓘ Quasiparticle of topological origin ⓘ |
| hasSpin | Half-integer spin ⓘ |
| hasTheoreticalTool |
Flux-smearing approximation
ⓘ
Chern–Simons theory ⓘ
surface form:
Mean-field Chern–Simons theory
|
| introducedBy | Jainendra K. Jain ⓘ |
| introducedInYear | 1989 ⓘ |
| movesIn | Reduced effective magnetic field ⓘ |
| obeysStatistics | Fermi–Dirac statistics ⓘ |
| observedIn |
GaAs/AlGaAs quantum wells
ⓘ
High-mobility semiconductor heterostructures ⓘ |
| playsRoleIn |
quantum Hall effect
ⓘ
surface form:
Fractional quantum Hall effect
|
| relatedConcept |
Anyons
ⓘ
Landau levels ⓘ
surface form:
Landau level
Laughlin quasiparticle ⓘ Quantum Hall ferromagnetism ⓘ |
| relatedTheory |
Composite fermion
self-linksurface differs
ⓘ
surface form:
Composite fermion theory
|
| studiedIn |
Condensed matter physics
ⓘ
quantum Hall effect ⓘ
surface form:
Quantum Hall systems
|
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: Composite fermion Description of subject: A composite fermion is a quasiparticle formed by an electron bound to an even number of magnetic flux quanta, playing a key role in explaining the fractional quantum Hall effect.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Composite fermion theory