We study the properties of the spinor wavefunction in a strongly disordered environment on a two-dimensional lattice. By employing a transfer-matrix calculation we find that there is a transition from delocalized to localized states at a critical value of the disorder strength. We prove that there exists an Anderson localized phase with exponentially decaying correlations for sufficiently strong scattering. Our results indicate that suppressed backscattering is not sufficient to prevent Anderson localization of surface states in topological insulators.
Uncorrelated disorder potential in one-dimensional lattice definitely induces Anderson localization, while quasiperiodic potential can lead to both localized and extended phases, depending on the potential strength. We investigate the Anderson localization in one-dimensional lattice with nonHermitian complex disorder and quasiperiodic potential. We present a non-Hermitian SSH chain to demonstrate that a nonzero imaginary disorder on-site potential can induce the standard Anderson localization. We also show that the non-Hermitian Aubry-Andre (AA) model exhibits a transition in parameter space, …
The article reviews the physics of Anderson localization on random regular graphs (RRG) and its connections to many-body localization (MBL) in disordered interacting systems. Properties of eigenstate and energy level correlations in delocalized and localized phases, as well at criticality, are discussed. In the many-body part, models with short-range and power-law interactions are considered, as well as the quantum-dot model representing the limit of the "most long-range" interaction. Central themes -- which are common to the RRG and MBL problems -- include ergodicity of the delocalized phase,…
Dynamical localization phenomena of monochromatically perturbed standard map (SM) and Anderson map (AM), which are both identified with a two-dimensional disordered system under suitable conditions, are investigated by the numerical wavepacket propagation. Some phenomenological formula of the dynamical localization length valid for wide range of control parameters are proposed for both SM and AM. For SM the formula completely agree with the experimentally established formula, and for AM the presence of a new regime of localization is confirmed. These formula can be derived by the self-consiste…
Dyson insulators with random hoppings in a lattice approach localization faster compared to the usual Anderson insulators with site disorder. For even-$N$ lattice sites the Dyson insulators mimic topological insulators with a pseudo-gap at the band center and the energy-level statistics obtained via the $P(S)$ distribution is of an intermediate type close to the Anderson localized Poisson limit. For odd-$N$ level-repulsion and Wigner statistics appears as in the quasi-metallic regime of $2D$ Anderson insulators, plus a single $E=0$ mode protected by chiral symmetry. The distribution of the par…
We study the Anderson localization in nonlinear systems by taking a nonlinear transmission line realizing the Toda lattice. It is found that the randomness in inductance induces the Anderson localization in the voltage propagation. Furthermore, the nonlinearity enhances the Anderson localization. They are understood in terms of attractive interactions to form a soliton in a nonlinear system. Our results will be applicable in general to the Anderson localization in nonlinear systems that have solitons.
We develop a real space cluster extension of the typical medium theory (cluster-TMT) to study Anderson localization. By construction, the cluster-TMT approach is formally equivalent to the real space cluster extension of the dynamical mean field theory. Applying the developed method to the 3D Anderson model with a box disorder distribution, we demonstrate that cluster-TMT successfully captures the localization phenomena in all disorder regimes. As a function of the cluster size, our method obtains the correct critical disorder strength for the Anderson localization in 3D, and systematically re…
Interplay of Flat-band and Anderson localizations in disordered moire superlattices
Guangxi University(广西大学);Anqing Normal University(安庆师范大学);Nankai University(南开大学);Nottingham Trent University(诺丁汉特伦特大学);East China Normal University(华东师范大学)
在过去的30年里,在三维(3D)无序样品中寻找光的安德森局域化产生了许多实验观察,这些观察最初被认为是成功的,然后被反对者争论,后来被他们的作者驳斥。这包括最近的结果,光在TiO_2粉末,T。Sperling等人现在表明是由于荧光而不是安德森局域化(New J. Phys. 18(2016)013039)。在3D中观察光的安德森局域化的困难可能是由于许多因素:无序材料的组分之间的光学对比度不足,近场效应等。克服这些困难的方法可能包括使用部分有序的材料,复杂结构的散射体,或冷原子云在磁场中。
We investigate the effect of spatially correlated disorder on the Anderson transition of phonons in three dimensions using a Greens function based approach, namely, the typical medium dynamical cluster approximation (TMDCA), in mass-disordered systems. We numerically demonstrate that correlated disorder with pairwise correlations mitigates the localization of the vibrational modes. A correlation driven localization-delocalization transition can emerge in a three-dimensional disordered system with an increase in the strength of correlations.
Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences(中国科学院物理研究所);University of Chinese Academy of Sciences(中国科学院大学);Shanghai University(上海大学);School of Physics and Astronomy, Shanghai Jiao Tong University(上海交通大学物理与天文学院)
Localization due to disorder has been one of the most intriguing theoretical concepts evolved in condensed matter. Here, we expand the theory of localization by considering two types of disorder at the same time, namely the original Anderson's disorder and the structural defect disorder, which has been suggested to be a key component in recently discovered two-dimensional amorphous materials. While increasing the degree of both disorders could induce localization of wavefunction in real space, we find that a small degree of structural defect disorder can significantly enhance the localization.…