# Exploiting ITO colloidal nanocrystals for ultrafast pulse generation

**Authors:** Qiangbing Guo, Yudong Cui, Yunhua Yao, Yuting Ye, Yue Yang, Xueming, Liu, Shian Zhang, Xiaofeng Liu, Jianrong Qiu, and Hideo Hosono

arXiv: 1701.07586 · 2020-06-02

## TL;DR

This paper demonstrates ultrafast pulse generation using solution-processed epsilon-near-zero nanocrystals, achieving response speeds over 2 THz and significant modulation depth, promising scalable photonic device applications.

## Contribution

It introduces a novel use of tunable ENZ nanocrystals for ultrafast photonic pulse generation, highlighting their high speed and modulation capabilities.

## Key findings

- Response speed >2 THz
- Modulation depth ~23%
- Potential for scalable photonic devices

## Abstract

Dynamical materials that capable of responding to optical stimuli have always been pursued for designing novel photonic devices and functionalities, of which the response speed and amplitude as well as integration adaptability and energy effectiveness are especially critical. Here we show ultrafast pulse generation by exploiting the ultrafast and sensitive nonlinear dynamical processes in tunably solution-processed colloidal epsilon-near-zero (ENZ) transparent conducting oxide (TCO) nanocrystals (NCs), of which the potential respond response speed is >2 THz and modulation depth is ~23% pumped at ~0.7 mJ/cm2, benefiting from the highly confined geometry in addition to the ENZ enhancement effect. These ENZ NCs may offer a scalable and printable material solution for dynamic photonic and optoelectronic devices.

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Source: https://tomesphere.com/paper/1701.07586