Memory effects in a vibrated thin granular layer

¹ Departamento de Física and Instituto de Computación Científica Avanzada (ICCAEx), Universidad de Extremadura, Avda. Elvas s/n 06071 Badajoz, Spain
² Departamento de Física Aplicada I, Universidad de Sevilla, C/ Virgen de Africa, 7 41011 Sevilla, Spain
³ Física Teórica, Universidad de Sevilla, Apartado de Correos 1065, 41080 Sevilla, Spain

^* e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 1 December 2025

Abstract

We present in this work the first experimental evidence of the thermal memory effect in a granular fluid. In particular, we observe here the Kovacs memory effect (an anomalous evolution of at least one macroscopic variable) in the granular temperature of the fluidized granular monolayer. The experimental setup consists here in a vertically shaken granular monolayer. The evolution of the granular temperature curves clearly displays the characteristic Kovacs humps. Furthermore, it appears that, at experimental level, the shaken monolayer displays the so-called anomalous Kovacs effec; i.e., and upwards hump for cool down protocol (or a downwards hump for a heating up process). The experimental results are also supported by molecular dynamics simulation data which use a realistic computational model for both the dynamics and tribology properties of the oscillatory top and bottom walls that are present in our laboratory.