The anisotropy induced by defects of "random local field" type in O(n) models and suppression of the Imry-Ma inhomogeneous state

Phase diagram for the O(n) model with defects of "random local field" type and verity of the Imry-Ma theorem

It is shown that the Imry-Ma theorem stating that in space dimensions d<4 the introduction of an arbitrarily small concentration of defects of the "random local field" type in a system with continuous symmetry of the n-component vector order parameter (O(n)model) leads to the long-range order collapse and to the occurrence of a disordered state, is not true if the anisotropic distribution of the defect-induced random local field directions in the n-dimensional space of the order parameter leads to the defect-induced effective anisotropy of the "easy axis" type. For a weakly anisotropic field d…

Cubic anisotropy created by defects of "random local anisotropy" type, and phase diagram of the O(n) model

The expression for the cubic-type-anisotropy constant created by defects of "random local anisotropy" type is derived. It is shown that the Imry-Ma theorem stating that in space dimensions d<4 the introduction of an arbitrarily small concentration of defects of the "random local anisotropy" type in a system with continuous symmetry of the n-component vector order parameter (O(n) model) leads to the long-range order collapse and to occurrence of a disordered state, is not true if an anisotropic distribution of the defect-induced random easy axes directions in the order parameter space creates a…

无序d波超导体中的非均匀序参量抑制

Inhomogeneous order-parameter suppression in disordered d-wave superconductors

本文报道了二维d波BCS超导体中无序效应的数值研究。我们比较精确的数值解的Bogoliubov-deGennes（BdG）方程的状态密度$ρ(E)$与标准的T-矩阵近似。在BdG方程的自洽解中，杂质位置附近的序参量的局部抑制导致非普适$α$在与单个杂质共振能量$Ω_0$相当的能量尺度上的表观幂律行为$ρ(E) \sim |E|^α$。我们发现，新的效果产生的静态空间之间的相关性的序参量和杂质分布。

作为空间非均匀能隙抑制的Peierls跃迁

Peierls transition as spatially inhomogeneous gap suppression

我们提出了一个模型的Peierls过渡（PT）考虑到振幅波动的电荷密度波和自发热激活抑制的Peierls间隙，类似于相位滑移过程。活化导致正相随温度升高呈指数增长。该模型较好地描述了在PT温度$T_P$以下和之上的电阻、热膨胀、杨氏模量和比热的行为。PT似乎具有独特的性质：它不包括作为参数的$T_P$，同时它具有一阶跃迁的特征。该模型的可能基础是激活的非相互作用振幅孤子扰动周围的大体积。

低掺杂陶瓷样品La_{2-x} Sr_{x}中反铁磁有序的抑制

Suppression of antiferromagnetic order in low-dopped ceramic samples La_{2-x}Sr_{x}CuO_{4}

揭示了锶杂质空间不均匀分布对陶瓷样品La 2-xSrxCuO 4反铁磁（AFM）有序温度的可能影响。

Topological protection, disorder, and interactions: Survival at the surface of 3D topological superconductors

We consider the interplay of disorder and interactions upon the gapless surface states of 3D topological superconductors. The combination of topology and superconducting order inverts the action of time-reversal symmetry, so that extrinsic time-reversal invariant surface perturbations appear only as "pseudomagnetic" fields (abelian and non-abelian vector potentials, which couple to spin and valley currents). The main effect of disorder is to induce multifractal scaling in surface state wavefunctions. These critically delocalized, yet strongly inhomogeneous states renormalize interaction matrix…