6533b838fe1ef96bd12a3beb
RESEARCH PRODUCT
Level statistics and Anderson delocalization in two-dimensional granular materials
Aile SunLing ZhangLing ZhangJie ZhengXulai SunYinqiao WangYujie WangJie ZhangWalter Schirmachersubject
PhysicsAnderson localizationFOS: Physical sciences02 engineering and technologyCondensed Matter - Soft Condensed Matter021001 nanoscience & nanotechnologyGranular material01 natural sciencesDebye frequencyDelocalized electronNormal mode0103 physical sciencesStatisticsExponentSoft Condensed Matter (cond-mat.soft)010306 general physics0210 nano-technologyScalingAnderson impurity modeldescription
Contrary to the theoretical predictions that all waves in two-dimensional disordered materials are localized, Anderson localization is observed only for sufficiently high frequencies in an isotropically jammed two-dimensional disordered granular packing of photoelastic disks. More specifically, we have performed an experiment in analyzing the level statistics of normal mode vibrations. We observe delocalized modes in the low-frequency boson-peak regime and localized modes in the high frequency regime with the crossover frequency just below the Debye frequency. We find that the level-distance distribution obeys Gaussian-Orthogonal-Ensemble (GOE) statistics, i.e. Wigner-Dyson distribution, in the boson-peak regime, whereas those in the high-frequency regime Poisson statistics is observed. The scenario is found to coincide with that of harmonic vibrational excitations in three-dimensional disordered solids.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2020-08-17 |