# Organic lateral heterostructures with interfacial fluctuation for polarization-resolved photonics

## TL;DR

Researchers developed a new method to create 2D organic lateral heterostructures with controlled interfacial fluctuation for polarization-resolved photonics.

## Contribution

A stepwise vapor-phase growth strategy enables precise control of 2D OLHs with noncoplanar epitaxial layers.

## Key findings

- Higher growth temperatures enhance molecular deposition and transition secondary components from in-plane to out-of-plane growth.
- Epitaxial layer thickness can be tuned from 20 to 800 nm using this method.
- The resulting OLHs show orthogonally polarized exciton conversion with dual photoluminescence emission bands.

## Abstract

Organic lateral heterostructures (OLHs) based on two-dimensional (2D) molecular crystals are formed through the coplanar assembly of multiple components, and they hold great promise for optoelectronic applications. However, the precise construction of 2D OLHs with noncoplanar epitaxial layers remains challenging, limiting further exploration of lateral heterojunctions. Here, we present a stepwise vapor-phase growth strategy for synthesizing 2D OLHs with interfacial fluctuation, forming convex, flat, and concave architectures. During the lateral epitaxial growth processes, higher growth temperatures enhance molecular deposition, driving the transition of the secondary component from in-plane to out-of-plane growth. Consequently, the epitaxial layer thickness is precisely tuned from 20 to 800 nm by increasing the growth temperature. The resulting OLHs exhibit orthogonally polarized exciton conversion, with dual photoluminescence emission bands at 450 and 670 nm, functioning as multimode photonic converters. These findings provide a strategy to regulate the epitaxial growth route of 2D OLHs, paving the way for integrated photonic circuits.

Two-dimensional lateral heterostructures with interfacial fluctuation can be used for polarization exciton conversion.