论文标题
电平动力和驱动无序量子点的水平交叉
Level dynamics and avoided level crossings in driven disordered quantum dots
论文作者
论文摘要
在两个二维无序量子点模型的情况下，研究了能量水平动力学动力学的统计特性，该模型最近邻居跳动受外部时间依赖性扰动。虽然在第一个模型中，外部驱动是通过现场能量的连续变化实现的，在第二个模型中，它是由抛物线电位的变形产生的。我们专注于潜力对定位性能的影响，并研究能量水平速度和曲率的统计数据，这些速度和曲率涉及其典型的大小和与随机矩阵理论（RMT）对高斯正交，统一，单位和符号结合的预测的一致性。此外，根据相应的Landau-Zener参数研究了避免水平交叉的统计特性。我们发现，Landau-Zener转变的强度表现出普遍的行为，这也意味着通用的单粒子动力学，可缓慢扰动，独立于疾病和潜在强度，系统大小和对称性类别。可以通过测量量子点中的单粒子能谱来实验验证这些结果。
The statistical properties of the dynamics of energy levels are investigated in the case of two two-dimensional disordered quantum dot models with nearest neighbor hopping subjected to external time-dependent perturbations. While in the first model the external drivings are realized by a continuous variation of the on-site energies, in the second one it is generated by deformations of a parabolic potential. We concentrate on the effects of the potential on the localization properties and investigate the statistics of the energy level velocities and curvatures regarding their typical magnitudes and domain of agreement with the predictions of Random Matrix Theory (RMT) for the Gaussian Orthogonal, Unitary and Symplectic ensembles. Moreover, the statistical properties of the avoided level crossings are investigated in terms of the corresponding Landau-Zener parameters. We find that the strength of the Landau-Zener transitions exhibits universal behavior which also implies universal single-particle dynamics for slow perturbations independent of the disorder and potential strength, the system size and the symmetry class. These results can be verified experimentally by measurements of single-particle energy spectra in quantum dots.
