Quantum Group, Bethe Ansatz and Bloch Electrons in a Magnetic Field
نویسندگان
چکیده
The wave functions for two dimensional Bloch electrons in a uniform magnetic field at the mid-band points are studied with the help of the algebraic structure of the quantum group Uq(sl2). A linear combination of its generators gives the Hamiltonian. We obtain analytical and numerical solutions for the wave functions by solving the Bethe Ansatz equations, proposed by Wiegmann and Zabrodin on the basis of above observation. The semi-classical case with the flux per plaquette φ = 1/Q is analyzed in detail, by exploring a structure of the Bethe Ansatz equations. We also reveal the multifractal structure of the Bethe Ansatz solutions and corresponding wave functions when φ is irrational, such as the golden or silver mean. PACS numbers: 72.15.Gd, 03.65.Fd
منابع مشابه
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