Helical Current for Rotation in Simple Four-Orbital Model

Abstract

Conjugated chains of carbon atoms (cumulenes) can produce helical current when coupled to external reservoirs.

The helical current can acquire angular momentum that can be used to drive the molecular rotation. We model this process using a simple four-orbital model with self-energy. We explore different parametrisations of the self-energy and note key properties in the energy space, such as symmetry of angular momentum density around the Fermi energy of the system.

We discuss the physical interpretations of the different self-energy parametrisations, such as different end-groups and chemical environments.