scholarly journals The temperature dependence of the conductivity peak values in the single and the double quantum well nanostructures n-InGaAs/GaAs after IR-illumination

2017 ◽  
Vol 51 (2) ◽  
pp. 281
Author(s):  
Yu.G. Arapov ◽  
S.V. Gudina ◽  
A.S. Klepikova ◽  
V.N. Neverov ◽  
G.I. Harus ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Quantum Wells ◽  
Quantum Hall Effect ◽  
Quantum Hall ◽  
Double Quantum ◽  
Integer Quantum Hall Effect ◽  
Double Quantum Well ◽  
Scaling Hypothesis ◽  
Integer Quantum ◽  
Two Parameter

The dependences of the longitudinal and Hall resistances on a magnetic field in n-InGaAs/GaAs heterostructures with a single and double quantum wells after infrared illumination are measured in the range of magnetic fields B=0-16 T and temperatures T=0.05-4.2 K. Analysis of the experimental results was carried out on a base of two-parameter scaling hypothesis for the integer quantum Hall effect. The value of the second (irrelevant) critical exponent of the theory of two-parameter scaling was estimated. DOI: 10.21883/FTP.2017.02.44119.8302

FURTHER EVIDENCE FOR A COLLAPSE OF THE EXCHANGE-ENHANCED SPIN SPLITTING IN TWO DIMENSIONAL SYSTEMS

2004 ◽  
Vol 18 (27n29) ◽  
pp. 3597-3602 ◽  
Author(s):  
B. A. PIOT ◽  
D. K. MAUDE ◽  
Z. R. WASILEWSKI ◽  
K. J. FRIEDLAND ◽  
R. HEY ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Quantum Wells ◽  
Quantum Hall Effect ◽  
Good Description ◽  
Quantum Hall ◽  
Exchange Interactions ◽  
Spin Splitting ◽  
Spin Gap ◽  
Integer Quantum Hall Effect ◽  
Integer Quantum

The collapse of spin splitting in the integer quantum Hall effect is investigated for a series of Al x Ga 1-x As / GaAs heterojunctions and quantum wells. Magnetoresistance measurements are performed at mK temperature, and a simple model is developed to simulate spin splitting. As expected a single-electron picture cannot reproduce the observed spin splitting, whereas a phenomenological enhanced-spin gap taking into account exchange interactions between electrons provides a good description. The phenomenological spin gap, which is linear in B at high magnetic field, collapses when the spin splitting collapses. This is consistent with previously proposed disorder-driven destruction of exchange interactions with decreasing magnetic field.

Scaling in the Quantum Hall Regime for a Double Quantum Well Nanostructure in High Magnetic Field

2014 ◽  
Vol 215 ◽  
pp. 208-213
Author(s):  
Yurii G. Arapov ◽  
Svetlana V. Gudina ◽  
Anna S. Klepikova ◽  
Vladimir N. Neverov ◽  
Sergey G. Novokshonov ◽  
...  
Keyword(s):  
Quantum Well ◽  
Hall Effect ◽  
Quantum Hall Effect ◽  
Quantum Hall ◽  
Electron Interaction ◽  
Double Quantum ◽  
Integer Quantum Hall Effect ◽  
Double Quantum Well ◽  
Scaling Hypothesis ◽  
Before And After

The longitudinal ρxx(B) and Hall ρxy(B) magnetoresistances are investigated in the integer quantum Hall effect regime in n-InGaAs/GaAs double quantum well nanostructures in the magnetic fields B up to 16 T at temperatures T = (0.05-4.2) K before and after IR illumination. The analysis of the quantum Hall effect plateau-plateau transitions based on the scaling hypothesis with regard to electron-electron interaction was carried out.

New Universality at the Magnetic Field Driven Insulator to Integer Quantum Hall Effect Transitions

1997 ◽  
Vol 78 (11) ◽  
pp. 2200-2203 ◽  
Author(s):  
S.-H. Song ◽  
D. Shahar ◽  
D. C. Tsui ◽  
Y. H. Xie ◽  
Don Monroe
Keyword(s):  
Magnetic Field ◽  
Hall Effect ◽  
Quantum Hall Effect ◽  
Quantum Hall ◽  
Integer Quantum Hall Effect ◽  
Integer Quantum ◽  
The Magnetic Field

scholarly journals Magnetoconductivity in quasiperiodic graphene superlattices

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
M. de Dios-Leyva ◽  
A. L. Morales ◽  
C. A. Duque
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Quantum Hall Effect ◽  
Quantum Hall ◽  
Oscillatory Behavior ◽  
Fermi Velocity ◽  
Perpendicular Magnetic Field ◽  
Self Similarity ◽  
Integer Quantum Hall Effect ◽  
Integer Quantum

AbstractThe magnetoconductivity in Fibonacci graphene superlattices is investigated in a perpendicular magnetic field B. It was shown that the B-dependence of the diffusive conductivity exhibits a complicated oscillatory behavior whose characteristics cannot be associated with Weiss oscillations, but rather with Shubnikov-de Haas ones. The absense of Weiss oscillations is attributed to the existence of two incommensurate periods in Fibonacci superlattices. It was also found that the quasiperiodicity of the structure leads to a renormalization of the Fermi velocity $$v_{F}$$ v F of graphene. Our calculations revealed that, for weak B, the dc Hall conductivity $$\sigma _{yx}$$ σ yx exhibits well defined and robust plateaux, where it takes the unexpected values $$\pm 4e^{2}/\hslash \left( 2N+1\right) $$ ± 4 e 2 / ℏ 2 N + 1 , indicating that the half-integer quantum Hall effect does not occur in the considered structure. It was finally shown that $$\sigma _{yx}$$ σ yx displays self-similarity for magnetic fields related by $$\tau ^{2}$$ τ 2 and $$\tau ^{4}$$ τ 4 , where $$\tau $$ τ is the golden mean.

scholarly journals On the equivalence between magnetic-field-induced phase transitions in the integer quantum Hall effect

2003 ◽  
Vol 126 (4) ◽  
pp. 197-201 ◽  
Author(s):  
C.F. Huang ◽  
Y.H. Chang ◽  
H.H. Cheng ◽  
Z.P. Yang ◽  
S.Y. Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Phase Transitions ◽  
Hall Effect ◽  
Quantum Hall Effect ◽  
Quantum Hall ◽  
Integer Quantum Hall Effect ◽  
Integer Quantum
Sign in / Sign up

Export Citation Format

Share Document