2021/02/28 by Sophie Marbach · 1 citation
Earth and Planetary Sciences · Engineering · Environmental Science · Mathematics · Physics and Astronomy · #Chemical physics #Computer science #Drop (telecommunication) #Geophysical and Geoelectrical Methods #Groundwater flow and contamination studies #Materials science #Mathematics #Nanopore #Nanopore and Nanochannel Transport Studies #Nanoporous #Nanotechnology #Noise (video) #Particle (ecology) #Physics #RADIUS #Scaling #Statistical physics #Telecommunications #cond-mat.soft
paper · pdf · doi:10.1063/5.0047380
arxiv created 2021/04/08 · openalex publication_date 2021/05/03 · arxiv updated 2021/05/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Fluctuations affect nanoporous transport in complex and intricate ways, making optimization of the signal-to-noise ratio in artificial designs challenging. Here, we focus on the simplest nanopore system, where non-interacting particles diffuse through a pore separating reservoirs. We find that the concentration difference between both sides (akin to the osmotic pressure drop) exhibits fractional noise in time t with mean square average that grows as t1/2. This originates from the diffusive exchange of particles from one region to another. We fully rationalize this effect, with particle simulations and analytic solutions. We further infer the parameters (pore radius and pore thickness) that control this exotic behavior. As a consequence, we show that the number of particles within the pore also exhibits fractional noise. Such fractional noise is responsible for noise spectral density scaling as 1/f3/2 with frequency f, and we quantify its amplitude. Our theoretical approach is applicable to more complex nanoporous systems (for example, with adsorption within the pore) and drastically simplifies both particle simulations and analytic calculus.