# Particle current rectification in a quasi-periodic double-stranded ladder

## TL;DR

This paper investigates particle current rectification in a double-stranded ladder network modeled after quasi-periodic DNA sequences, demonstrating nearly 100% rectification and tunable phase, with robustness against temperature and electron interactions.

## Contribution

It introduces a generalized NEGF-based approach to achieve high rectification in quasi-periodic double-stranded systems, applicable to biomolecular and nanoscale devices.

## Key findings

- Almost 100% current rectification at low bias
- Rectification phase can be tuned via Fermi energy and AAH phase
- Robust rectification persists with moderate temperature and electron interactions

## Abstract

We report transport properties and particle current rectification operation in a double-stranded tight-binding ladder network within non-equilibrium Green's function (NEGF) formalism that can easily be generalized in multi-stranded systems. First, we explore the rectification operation considering the model of an artificial double-stranded DNA (dsDNA) molecular system with Fibonacci type substitutional sequence. Substitutional sequences form quasi-periodic potentials. This analysis may shed new light in designing efficient nanoscale rectifier. It can also be directly implemented to different biomolecular systems like nucleic acids and most proteins as they follow quasi-periodic orders. Motivated with this fact, we consider different configurations depending on the choices of on-site energies and/or inter or intra strand nearest-neighbor hopping integrals in the form of Aubry-Andr\'{e}-Harper (AAH) model (that also obeys quasi-periodic order), and in all the cases we find almost $100\%$ current rectification even at very low bias region. Along with this, we observe that the phase (positive or negative) of rectification can suitably be engineered by tuning the Fermi energy and AAH phase. The effects of electron-electron (e-e) interaction and temperature are also studied, which show that a reasonably large rectification can be observed even for moderate temperature range and e-e interaction strength.