Asymmetric hot-carrier thermalization and broadband photoresponse in graphene-2D semiconductor lateral heterojunctions

The massless Dirac electron transport in graphene has led to a variety of unique light-matter interaction phenomena, which promise many novel optoelectronic applications. Most of the effects are only accessible by breaking the spatial symmetry, through introducing edges, p-n junctions, or heterogene...

Full description

Bibliographic Details
Main Authors: Lin, Yuxuan, Ma, Qiong, Shen, Pin-Chun, Ilyas, Batyr, Bie, Yaqing, Liao, Albert D., Ergecen, Emre, Han, Bingnan, Mao, Nannan, Zhang, Xu, Ji, Xiang, Zhang, Yuhao, Yin, Jihao, Huang, Shengxi, Dresselhaus, Mildred, Gedik, Nuh, Jarillo-Herrero, Pablo, Ling, Xi, Kong, Jing, Palacios, Tomas
Other Authors: Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Format: Article
Language:English
Published: American Association for the Advancement of Science (AAAS) 2019
Online Access:https://hdl.handle.net/1721.1/121449
Description
Summary:The massless Dirac electron transport in graphene has led to a variety of unique light-matter interaction phenomena, which promise many novel optoelectronic applications. Most of the effects are only accessible by breaking the spatial symmetry, through introducing edges, p-n junctions, or heterogeneous interfaces. The recent development of direct synthesis of lateral heterostructures offers new opportunities to achieve the desired asymmetry. As a proof of concept, we study the photothermoelectric effect in an asymmetric lateral heterojunction between the Dirac semimetallic monolayer graphene and the parabolic semiconducting monolayer MoS2. Very different hot-carrier cooling mechanisms on the graphene and the MoS2 sides allow us to resolve the asymmetric thermalization pathways of photoinduced hot carriers spatially with electrostatic gate tunability. We also demonstrate the potential of graphene-2D semiconductor lateral heterojunctions as broadband infrared photodetectors. The proposed structure shows an extreme in-plane asymmetry and provides a new platform to study light-matter interactions in low-dimensional systems.