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arXiv · 1211.5641

Universal scheme to generate metal-insulator transition in disordered systems

Ai-Min Guo·Shi-Jie Xiong·X. C. Xie·Qing-feng Sun
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Abstract

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.

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Ai-Min Guo, Shi-Jie Xiong, X. C. Xie, Qing-feng Sun. 2012-11-24. Universal scheme to generate metal-insulator transition in disordered systems. https://doi.org/10.1088/0953-8984%2F25%2F41%2F415501

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