# Switching behaviour of stilbene molecular device: a first-principles study

## TL;DR

This study uses first-principles NEGF calculations to analyze the switching behavior of stilbene molecular devices, demonstrating their potential as optically controlled molecular switches based on cis-trans isomerization.

## Contribution

It provides a detailed first-principles investigation of stilbene's switching mechanism, highlighting the electronic differences between cis and trans isomers under bias.

## Key findings

- Cis-isomers transfer more electrons under optical excitation.
- Trans-stilbene exhibits lower current magnitude than cis-stilbene.
- Both isomers can function as molecular switches.

## Abstract

The switching behaviour of stilbene molecular system (SMS) device is investigated with the help of non-equilibrium Green's function (NEGF) approach using first principles calculation. The transmission spectrum of cis-isomers confirmed that more electrons are transferred across the SMS-device using optical excitation by the spin of C$=$C bond by torsion angle $(\theta=180^\circ)$. The current-voltage characteristics show the lower magnitude of current for trans-stilbene and higher magnitude of current for cis-stilbene for an externally applied bias voltage. The outcome of the proposed work suggests that cis and trans-stilbene molecular device can be used as a switch.