Density of States Proportion on Charge Transfer Kinetics in Breathing Fermionic Systems of Molecules and Materials: A Perspective of Entropy-Ruled Method

TL;DR

This paper introduces an entropy-ruled charge dynamics method that unifies band and hopping transport mechanisms via a DOS proportion, providing a new descriptor for charge transport in molecular and material systems.

Contribution

It proposes a novel entropy-ruled formalism based on DOS proportion that bridges different charge transport regimes and discusses its validity and potential applications.

Findings

DOS proportion correlates with charge transport quantities

The method unifies band and hopping transport mechanisms

Limitations of classical approaches are analyzed

Abstract

Conceptualization, theory, method developments and implementations are always of great importance and an interesting task to explore a new dimension in science and technology, which is highly solicited for various functional-driven potential applications (e.g., electronic devices, charge storage devices). Numerous experimental and theoretical studies urge the necessity of a new theory or method to quantify the exact value of charge transport (CT) calculations (e.g., mobility and conductivity) through the appropriate process and methods. With this motivation, the entropy-ruled charge dynamics method has been recently proposed, which unifies band and hopping transport mechanism via quantum-classical transition analogy. Here, the energy (in terms of chemical potential) scaled entropy has a direct proportion with the density of states (DOS); and hence it is termed as DOS proportion. This proportion principally acts as a key descriptor for charge transport calculations in both molecular and materials systems, which is directly connected with all CT quantities like mobility, conductivity, current density etc. This perspective explains a unique nature of entropy-ruled method for the entire transport range from delocalized band to localization (or hopping) transport. The validity and limitations of Einstein relation and Boltzmann approach are discussed with different limits and physical conditions for disordered molecules and periodic systems. Finally, the futuristic scope and expected progress is addressed for correlated electron dynamical systems and devices. It is well-noted that the new DOS proportion and related entropy-ruled transport formalism are fundamentally more important for nurturing semiconducting science and technology towards a new era.