秋元研D1の堺君による Physical Review E に出版された以下の論文の解説動画です。
Unexpected effects of disorder on current fluctuations in the symmetric simple exclusion process
Issei Sakai and Takuma Akimoto
Phys. Rev. E 111, 014134 – Published 16 January, 2025
DOI: https://doi.org/10.1103/PhysRevE.111.014134
abstract: We explore how the disorder impacts the current fluctuations in the symmetric simple exclusion process (SSEP) within a heterogeneous environment. First, we analyze the SSEP with a defect site under the periodic boundary conditions. We derive the exact expression for the second moment of the current and observe deviations from that of the homogeneous system. Notably, the second moment of the current shows asymmetric density dependence around a density of 1/2 and surpassing that of the homogeneous system in the low-density region. Furthermore, based on the finding from the SSEP with a defect site, we present an approximate derivation of the second moment of the current in the SSEP on a quenched random energy landscape using a partial-mean-field approach. The second moment of the current is heavily influenced by the energy landscape, revealing unique effects arising from the interplay between the heterogeneous environment and the many-body system. Our findings provide valuable insights that can be applied to control current fluctuations in systems involving the interactions of many particles, such as biological transport.
0:14 single file diffusion
0:40 対称単純排他過程
3:02 狭い筒の中の水分子の拡散
3:44 不均一環境下での単一粒子の拡散
6:55 不均一環境下での single-file diffusion
7:55 本研究の目的
8:38 単一の欠陥を伴う対称単純排他過程
9:07 トータルカレントの２次モーメント
12:33 Quenched random energy landscape 上の対称単純排他過程
13:05 Partial-mean-field approach
14:05 トータルカレントの２次モーメント
16:22 Summary