quantum Hall effect
E545049
The quantum Hall effect is a quantum phenomenon in two-dimensional electron systems where the Hall conductance becomes quantized in integer or fractional values, revealing fundamental aspects of condensed matter physics and enabling precise resistance standards.
All labels observed (5)
| Label | Occurrences |
|---|---|
| quantum Hall effect canonical | 3 |
| fractional quantum Hall effect | 2 |
| Fractional quantum Hall effect | 1 |
| Fractional quantum Hall regime | 1 |
| Quantum Hall systems | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T5775145 — 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: quantum Hall effect Context triple: [Klaus von Klitzing, hasDiscovered, quantum Hall effect]
-
A.
Shubnikov–de Haas effect
The Shubnikov–de Haas effect is a quantum oscillatory phenomenon in the electrical resistance of conductors and semiconductors subjected to strong magnetic fields at low temperatures, used to probe their electronic structure and Fermi surface.
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B.
de Haas–van Alphen effect
The de Haas–van Alphen effect is a quantum oscillatory phenomenon in metals where the magnetization varies periodically with applied magnetic field, allowing precise mapping of the electronic structure and Fermi surface.
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C.
Aharonov–Casher effect
The Aharonov–Casher effect is a quantum mechanical phenomenon in which a neutral particle with a magnetic moment acquires a measurable phase shift when moving around a line of electric charge, illustrating the significance of electromagnetic potentials.
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D.
Composite fermion
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.
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E.
Aharonov–Bohm effect
The Aharonov–Bohm effect is a quantum mechanical phenomenon in which charged particles are influenced by electromagnetic potentials in regions where the classical electromagnetic fields are zero, revealing the physical significance of potentials in quantum theory.
- 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: quantum Hall effect Target entity description: The quantum Hall effect is a quantum phenomenon in two-dimensional electron systems where the Hall conductance becomes quantized in integer or fractional values, revealing fundamental aspects of condensed matter physics and enabling precise resistance standards.
-
A.
Shubnikov–de Haas effect
The Shubnikov–de Haas effect is a quantum oscillatory phenomenon in the electrical resistance of conductors and semiconductors subjected to strong magnetic fields at low temperatures, used to probe their electronic structure and Fermi surface.
-
B.
de Haas–van Alphen effect
The de Haas–van Alphen effect is a quantum oscillatory phenomenon in metals where the magnetization varies periodically with applied magnetic field, allowing precise mapping of the electronic structure and Fermi surface.
-
C.
Aharonov–Casher effect
The Aharonov–Casher effect is a quantum mechanical phenomenon in which a neutral particle with a magnetic moment acquires a measurable phase shift when moving around a line of electric charge, illustrating the significance of electromagnetic potentials.
-
D.
Composite fermion
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.
-
E.
Aharonov–Bohm effect
The Aharonov–Bohm effect is a quantum mechanical phenomenon in which charged particles are influenced by electromagnetic potentials in regions where the classical electromagnetic fields are zero, revealing the physical significance of potentials in quantum theory.
- F. None of above. chosen
Statements (56)
| Predicate | Object |
|---|---|
| instanceOf |
condensed matter physics phenomenon
ⓘ
quantum phenomenon ⓘ topological phase of matter ⓘ |
| awarded | Nobel Prize in Physics 1985 to Klaus von Klitzing NERFINISHED ⓘ |
| characterizedBy |
formation of Landau levels
ⓘ
quantized Hall conductance ⓘ topologically protected edge states ⓘ vanishing longitudinal resistance ⓘ |
| discoveredAt | High Magnetic Field Laboratory in Grenoble NERFINISHED ⓘ |
| discoveredBy | Klaus von Klitzing NERFINISHED ⓘ |
| discoveryYear | 1980 ⓘ |
| field |
condensed matter physics
ⓘ
low-temperature physics ⓘ mesoscopic physics ⓘ |
| hasApplication |
metrology
ⓘ
quantum standards of resistance ⓘ study of topological phases of matter ⓘ |
| hasConsequence |
plateaus in Hall resistance
ⓘ
precise electrical resistance standard ⓘ quantization of Hall resistance ⓘ robustness against disorder ⓘ zero longitudinal resistivity on plateaus ⓘ |
| hasGeneralization |
fractional quantum Hall effect
NERFINISHED
ⓘ
higher-dimensional quantum Hall effect ⓘ quantum anomalous Hall effect ⓘ |
| hasType |
fractional quantum Hall effect
ⓘ
integer quantum Hall effect NERFINISHED ⓘ |
| involves |
disorder-induced localization
ⓘ
electron–electron interactions ⓘ strong electron–magnetic field coupling ⓘ |
| modelledBy |
Chern–Simons field theory
NERFINISHED
ⓘ
Landau level theory NERFINISHED ⓘ Laughlin wavefunction NERFINISHED ⓘ |
| occursIn |
GaAs/AlGaAs heterojunctions
ⓘ
MOSFET inversion layers ⓘ graphene NERFINISHED ⓘ semiconductor heterostructures ⓘ two-dimensional electron systems ⓘ |
| quantizedHallConductance |
integer multiples of e^2/h
ⓘ
rational fractions of e^2/h ⓘ |
| relatedTo |
Anderson localization
NERFINISHED
ⓘ
Berry phase ⓘ Chern number ⓘ Landau quantization NERFINISHED ⓘ anyons ⓘ edge–bulk correspondence ⓘ quantum anomalous Hall effect ⓘ quantum spin Hall effect ⓘ spin Hall effect ⓘ topological invariants ⓘ topological order ⓘ |
| requires |
low temperature
ⓘ
strong perpendicular magnetic field ⓘ |
| usedAs |
realization of von Klitzing constant
ⓘ
resistance standard ⓘ |
| usedFor | high-precision measurement of fine-structure constant ⓘ |
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: quantum Hall effect Description of subject: The quantum Hall effect is a quantum phenomenon in two-dimensional electron systems where the Hall conductance becomes quantized in integer or fractional values, revealing fundamental aspects of condensed matter physics and enabling precise resistance standards.
Referenced by (8)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
fractional quantum Hall effect
this entity surface form:
fractional quantum Hall effect
this entity surface form:
Fractional quantum Hall regime
this entity surface form:
Fractional quantum Hall effect
this entity surface form:
Quantum Hall systems