scholarly journals Electromagnetic response and pseudo-zero-mode Landau levels of bilayer graphene in a magnetic field

2008 ◽  
Vol 77 (19) ◽  
Author(s):  
T. Misumi ◽  
K. Shizuya
Keyword(s):  
Magnetic Field ◽  
Zero Mode ◽  
Bilayer Graphene ◽  
Landau Levels ◽  
Electromagnetic Response

scholarly journals GRAPHENE: KINKS, SUPERLATTICES, LANDAU LEVELS AND MAGNETOTRANSPORT

2012 ◽  
Vol 26 (21) ◽  
pp. 1242007 ◽  
Author(s):  
MATTHEW KILLI ◽  
SI WU ◽  
ARUN PARAMEKANTI
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Bilayer Graphene ◽  
Landau Levels ◽  
Monolayer Graphene ◽  
Dirac Fermion ◽  
Type Device ◽  
Wide Range ◽  
Switching Type ◽  
Device Applications

We review recent work on superlattices in monolayer and bilayer graphene. We highlight the role of the quasiparticle chirality in generating new Dirac fermion modes with tunable anisotropic velocities in one dimensional (1D) superlattices in both monolayer and bilayer graphene. We discuss the structure of the Landau levels and magnetotransport in such superlattices over a wide range of perpendicular (orbital) magnetic fields. In monolayer graphene, we show that an orbital magnetic field can reverse the anisotropy of the transport imposed by the superlattice potential, suggesting possible switching-type device applications. We also consider topological modes localized at a kink in an electric field applied perpendicular to bilayer graphene, and show how interactions convert these modes into a two-band Luttinger liquid with tunable Luttinger parameters. The band structures of electric field superlattices in bilayer graphene (with or without a magnetic field) are shown to arise naturally from a coupled array of such topological modes. We briefly review some bandstructure results for 2D superlattices. We conclude with a discussion of recent tunneling and transport experiments and point out open issues.

ECHO EFFECTS ON RELATIVISTIC LANDAU LEVELS IN GRAPHENE AND BIGRAPHENE AS A MANIFESTATION OF THE QUANTUM MEMORY

2012 ◽  
Vol 26 (15) ◽  
pp. 1250094 ◽  
Author(s):  
MIKHAIL B. BELONENKO ◽  
ALEXANDER V. ZHUKOV ◽  
KONSTANTIN É. NEMCHENKO ◽  
SANJAY PRABHAKAR ◽  
RODERICK MELNIK
Keyword(s):  
Magnetic Field ◽  
Far Infrared ◽  
Infrared Region ◽  
Bilayer Graphene ◽  
Quantum Memory ◽  
Landau Levels ◽  
Wave Approximation ◽  
Long Wave ◽  
Quantizing Magnetic Field ◽  
Long Wave Approximation

We consider the echo effects, which can take place in graphene and bigraphene (bilayer graphene), when the system of relativistic Landau levels in a quantizing magnetic field appears. Graphene (bigraphene) is examined theoretically in the long-wave approximation near the Dirac points. We propose to use the echo effects for realization of quantum memory for optical states in the far-infrared region.

MATHEMATICAL MODELING OF TEMPERATURE EFFECT ON THE FAN CHART OF MAGNETOABSORPTION SPECTRUM IN SEMICONDUCTORS

2019 ◽  
pp. 104-115
Author(s):  
G. Gulyamov ◽  
U. I. Erkaboev ◽  
A. G. Gulyamov
Keyword(s):  
Mathematical Modeling ◽  
Magnetic Field ◽  
Temperature Dependence ◽  
Density Of States ◽  
Landau Levels ◽  
Joint Density ◽  
Narrow Gap ◽  
Narrow Gap Semiconductors ◽  
Dispersion Law ◽  
The Magnetic Field

The article considers the oscillations of interband magneto-optical absorption in semiconductors with the Kane dispersion law. We have compared the changes in oscillations of the joint density of states with respect to the photon energy for different Landau levels in parabolic and non-parabolic zones. An analytical expression is obtained for the oscillation of the combined density of states in narrow-gap semiconductors. We have calculated the dependence of the maximum photon energy on the magnetic field at different temperatures. A theoretical study of the band structure showed that the magnetoabsorption oscillations decrease with an increase in temperature, and the photon energies nonlinearly depend on a strong magnetic field. The article proposes a simple method for calculating the oscillation of joint density of states in a quantizing magnetic field with the non-quadratic dispersion law. The temperature dependence of the oscillations joint density of states in semiconductors with non-parabolic dispersion law is obtained. Moreover, the article studies the temperature dependence of the band gap in a strong magnetic field with the non-quadratic dispersion law. The method is applied to the research of the magnetic absorption in narrow-gap semiconductors with nonparabolic dispersion law. It is shown that as the temperature increases, Landau levels are washed away due to thermal broadening and density of states turns into a density of states without a magnetic field. Using the mathematical model, the temperature dependence of the density distribution of energy states in strong magnetic fields is considered. It is shown that the continuous spectrum of the density of states, measured at the temperature of liquid nitrogen, at low temperatures turns into discrete Landau levels. Mathematical modeling of processes using experimental values of the continuous spectrum of the density of states makes it possible to calculate discrete Landau levels. We have created the three-dimensional fan chart of magneto optical oscillations of semiconductors with considering for the joint density of energy states. For a nonquadratic dispersion law, the maximum frequency of the absorbed light and the width of the forbidden band are shown to depend nonlinearly on the magnetic field. Modeling the temperature  dependence allowed us to determine the Landau levels in semiconductors in a wide temperature spectrum. Using the proposed model, the experimental results obtained for narrow-gap semiconductors are analyzed. The theoretical results are compared with experimental results.

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