In a recent paper [Physical Review B 95, 165428 (2019)], M. Saiz-Bretín et al argue that graphene nanorings attached to two leads show increased phonon scattering while keeping good electron transport. Using a density-functional parametrized tight-binding method combined with Green’s function technique, they show that the lattice thermal conductance is largely reduced as compared to that of graphene nanoribbons. At the same time, numerical calculations based on the quantum transmission boundary method, combined with an effective transfer matrix method, predict that the electric properties are not considerably deteriorated, leading to an overall remarkable thermoelectric efficiency. They conclude that graphene nanorings can be regarded as promising candidates for nanoscale thermoelectric devices.

In a recent paper [Physical Review E 98, 052221 (2018)], E. Díaz et al introduce an effective model for electron transport in a deformable helical molecular lattice that resembles the nonlinear Kronig-Penney model in the adiabatic approximation. In addition, the continuum limit of the model is achieved when the dipole-dipole distance is smaller than the spatial extent of the bright soliton, as discussed by E. Díaz et al. [N. J. Phys. 20, 043055 (2018)]. In this limit, the model reduces to an extended Davydov model. Finally, they also focus on perturbations to the bright soliton that arise naturally in the context of real helical molecules. They conclude that the continuum approximation provides excellent results in more complex scenarios.

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