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Hofstadter Butterfly. Chene Tradunsky & Or Cohen with the great help of Ariel Amir. Using "Tight Binding" method we created a matrix representing the Hamiltonian for the entire lattice ( Size - N 2 *N 2 ) After finding Eigen Values and Eigen States we got…. Square Lattice of Atoms.
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Hofstadter Butterfly Chene Tradunsky & Or Cohen with the great help of Ariel Amir
Using "Tight Binding" method we created a matrix representing the Hamiltonian for the entire lattice ( Size - N2*N2) After finding Eigen Values and Eigen States we got… Square Lattice of Atoms
Energy Band in Various Magnitic Fields – Butterfly in Square Lattice E0+4t E E0 E0-4t B
Evolution of an eigen state - Notice the edge states that don't exist for calculations infinite N E B
Classical Explanation for Edge States Magnetron Radius
Same method – “Tight Binding”, putting in a matrix… but look what happens now ! Hexagonal Lattice
Hexagonal Butterfly E E0+4t E0 E0-4t 0.2 0.4 0.6 0.8 1.0 B
Some physical explanationfor Low Magnetic Field Dispersion in square lattice (B=0) : Behaves like free particle in 2D with effective mass ! Free particle in homogenous magnetic field receives extra energy – Landau Levels :
What happens in hexagonal lattice ? Dispersion in square lattice (B=0) : For certain K behaves like relativistic particle : A correction to the energy can be calculated which is similar to the Landau Levels :