Light matter interaction in WS$_{2}$ nanotube-graphene hybrid devices

TL;DR

This study investigates how hybrid devices made of WS$_{2}$ nanotubes and graphene interact with light, revealing how device engineering and defects influence photocurrent generation and efficiency.

Contribution

It demonstrates that engineering graphene electrodes and utilizing defects can enhance and tune photocarrier generation in WS$_{2}$ nanotube-graphene hybrids.

Findings

Photocurrent response is inhomogeneous across the device.

External quantum efficiency is approximately 1% at 0 V bias.

Defects can be used to improve and control photocarrier generation.

Abstract

We study the light matter interaction in WS$_{2}$ nanotube-graphene hybrid devices. Using scanning photocurrent microscopy we find that by engineering graphene electrodes for WS$_{2}$ nanotubes we can improve the collection of photogenerated carriers. We observe inhomogeneous spatial photocurrent response with an external quantum efficiency of $\sim 1\%$ at 0 V bias. We show that defects play an important role and can be utilized to enhance and tune photocarrier generation.