Tuesday, November 27, 2012

1211.5641 (Ai-Min Guo et al.)

Universal scheme to generate metal-insulator transition in disordered

Ai-Min Guo, Shi-Jie Xiong, X. C. Xie, Qing-feng Sun
We propose a scheme to generate metal-insulator transition in random binary layer (RBL) model, which is constructed by randomly assigning two types of layers. Based on a tight-binding Hamiltonian, the localization length is calculated for a variety of RBLs with different cross section geometries by using the transfer-matrix method. Both analytical and numerical results show that a band of extended states could appear in the RBLs and the systems behave as metals by properly tuning the model parameters, due to the existence of a completely ordered subband, leading to a metal-insulator transition in parameter space. Furthermore, the extended states are irrespective of the diagonal and off-diagonal disorder strengths. Our results can be generalized to two- and three-dimensional disordered systems with arbitrary layer structures, and may be realized in Bose-Einstein condensates.
View original: http://arxiv.org/abs/1211.5641

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