NETWORK MODELS OF QUANTUM PERCOLATION AND THEIR FIELD-THEORY REPRESENTATIONS

Article

关键词: LOWEST LANDAU-LEVEL;    MAGNETIC-FIELD;    SPIN CHAINS;    HALL;    DELOCALIZATION;    LOCALIZATION;    CONDUCTANCE;    TRANSITION;    INSULATOR;    THETA=PI;   

DOI  :  10.1103/PhysRevB.50.10788

来源: SCIE

【 摘 要 】

We obtain the field-theory representations of several network models that are relevant to two-dimensional transport in high magnetic fields. Among them, the simplest one, which is relevant to the plateau transition in the quantum Hall effect, is equivalent to a particular representation of an antiferromagnetic SU(2N) (N-->0) spin chain. Since the latter can be mapped onto a theta not equal 0, U(2N)/U(N)XU(N) a model, and since recent numerical analyses of the corresponding network give a delocalization transition with nu approximate to 2.3, we conclude that the same exponent is applicable to the a model.

【 授权许可】

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