TY  - JOUR
A1  - Petreska, Irina
A1  - Pejov, Ljupco
A1  - Sandev, Trifce
A1  - Kocarev, Ljupčo
A1  - Metzler, Ralf
T1  - Tuning of the dielectric relaxation and complex susceptibility in a system of polar molecules: a generalised model based on rotational diffusion with resetting
JF  - Fractal and fractional
N2  - The application of the fractional calculus in the mathematical modelling of relaxation processes in complex heterogeneous media has attracted a considerable amount of interest lately. 
The reason for this is the successful implementation of fractional stochastic and kinetic equations in the studies of non-Debye relaxation. 
In this work, we consider the rotational diffusion equation with a generalised memory kernel in the context of dielectric relaxation processes in a medium composed of polar molecules. We give an overview of existing models on non-exponential relaxation and introduce an exponential resetting dynamic in the corresponding process. 
The autocorrelation function and complex susceptibility are analysed in detail. 
We show that stochastic resetting leads to a saturation of the autocorrelation function to a constant value, in contrast to the case without resetting, for which it decays to zero. The behaviour of the autocorrelation function, as well as the complex susceptibility in the presence of resetting, confirms that the dielectric relaxation dynamics can be tuned by an appropriate choice of the resetting rate. 
The presented results are general and flexible, and they will be of interest for the theoretical description of non-trivial relaxation dynamics in heterogeneous systems composed of polar molecules.
KW  - rotational diffusion
KW  - memory kernel
KW  - Fokker-Planck equation
KW  - non-exponential relaxation
KW  - autocorrelation function
KW  - complex
KW  - susceptibility
Y1  - 2022
U6  - https://doi.org/10.3390/fractalfract6020088
SN  - 2504-3110
VL  - 6
IS  - 2
PB  - MDPI AG, Fractal Fract Editorial Office
CY  - Basel
ER  -