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arXiv 1908.030512019-08quant-phcond-mat.dis-nncond-mat.mes-hall

Quantum percolation in quasicrystals using continuous-time quantum walk

Prateek Chawla, C. V. Ambarish, C. M. Chandrashekar

备注：: 9 pages, 14 figures
发表信息：: J. Phys. Commun. 3 125004 (2019)
DOI：: 10.1088/2399-6528/ab5ce0

英文摘要：

We study the percolation of a quantum particle on quasicrystal lattices and compare it with the square lattice. For our study, we have considered quasicrystal lattices modelled on the pentagonally symmetric Penrose tiling and the octagonally symmetric Ammann-Beenker tiling. The dynamics of the quantum particle is modelled using continuous-time quantum walk (CTQW) formalism. We present a comparison of the behaviour of the CTQW on the two aperiodic quasicrystal lattices and the square lattice when all the vertices are connected and when disorder is introduced in the form of disconnections between the vertices. Unlike on a square lattice, we see a significant fraction of quantum state localised around the origin in quasicrystal lattice. With increase in disorder, the percolation probability of a particle on a quasicrystal lattice decreases significantly faster when compared to the square lattice. This study sheds light on the minimum fraction of disconnections allowed to see percolation of quantum particle on these quasicrystal lattices.

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