Collapse of quantized Hall resistance and breakdown of dissipationless state in the integer quantum Hall effect: filling factor dependence

Formation of the electron state with the integer filling factor was studied by magneto-capacitance and magneto-photoluminescence measurements in weakly coupled GaAs/AlGaAs multilayers where quasi-two dimensional electrons revealed the integer Quantum Hall Effect. The disorder modulated compressibility of the quantized Hall phase with the filling factor ν=2 was determined. The incompressible fraction of this phase was shown to rapidly disappear with the increasing temperature. The quantized Hall phase of the weakly coupled multilayers was shown to emit the asymmetrical photoluminescence lines. We demonstrated that the observed asymmetry is caused by a partial population of the extended electron states formed in the quantized Hall conductor phase due to the disorder induced interlayer tunneling.

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THE CONNECTION BETWEEN INTEGER QUANTUM HALL EFFECT AND FRACTIONAL QUANTUM HALL EFFECT

Modern Physics Letters B ◽

10.1142/s0217984907012530 ◽

2007 ◽

Vol 21 (02n03) ◽

pp. 109-113

Author(s):

JE HUAN KOO ◽

GUANGSUP CHO

Keyword(s):

Hall Effect ◽

Quantum Hall Effect ◽

Quantum Hall ◽

Fractional Quantum Hall Effect ◽

Matter Wave ◽

Hall Resistance ◽

Fractional Quantum ◽

Fractional Quantum Hall ◽

Integer Quantum Hall Effect ◽

Integer Quantum

We investigate the integer quantum Hall effect (IQHE) and the fractional quantum Hall effect (FQHE). We derive the quantized Hall resistance of IQHE in the presence of the high magnetic field using the scheme of standing waves by de Broglie matter wave of electron gas confined within a two-dimensional square-type quantum well. Without any modification of electrons and holes, it is shown that FQHE is only a decoupling mode of the Hall resistance by two-band-type of electrons and holes, which are governed by IQHE respectively.

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An all-epitaxial nitride heterostructure with concurrent quantum Hall effect and superconductivity

Science Advances ◽

10.1126/sciadv.abf1388 ◽

2021 ◽

Vol 7 (8) ◽

pp. eabf1388

Author(s):

Phillip Dang ◽

Guru Khalsa ◽

Celesta S. Chang ◽

D. Scott Katzer ◽

Neeraj Nepal ◽

...

Keyword(s):

Hall Effect ◽

Quantum Hall Effect ◽

Electron Gas ◽

Quantum Hall ◽

High Electron Mobility Transistor ◽

High Electron ◽

2D Electron Gas ◽

Integer Quantum Hall Effect ◽

Topological Quantum ◽

Integer Quantum

Creating seamless heterostructures that exhibit the quantum Hall effect and superconductivity is highly desirable for future electronics based on topological quantum computing. However, the two topologically robust electronic phases are typically incompatible owing to conflicting magnetic field requirements. Combined advances in the epitaxial growth of a nitride superconductor with a high critical temperature and a subsequent nitride semiconductor heterostructure of metal polarity enable the observation of clean integer quantum Hall effect in the polarization-induced two-dimensional (2D) electron gas of the high-electron mobility transistor. Through individual magnetotransport measurements of the spatially separated GaN 2D electron gas and superconducting NbN layers, we find a small window of magnetic fields and temperatures in which the epitaxial layers retain their respective quantum Hall and superconducting properties. Its analysis indicates that in epitaxial nitride superconductor/semiconductor heterostructures, this window can be significantly expanded, creating an industrially viable platform for robust quantum devices that exploit topologically protected transport.

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