Issue 30, 2017
From the journal:

Nanoscale

Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2†

Youngsin Park,‡a   Sang Wook Han,‡b   Christopher C. S. Chan,c   Benjamin P. L. Reid,c   Robert A. Taylor,*c   Nammee Kim,d   Yongcheol Jo,e   Hyunsik Im ORCID logo *e  and  Kwang S. Kim ORCID logo *a  

* Corresponding authors

a Department of Chemistry and Physics, School of Natural Science, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea
E-mail: kimks@unist.ac.kr

b Department of Physics and Energy Harvest & Storage Research Center, University of Ulsan, Ulsan 44610, Korea

c Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
E-mail: robert.taylor@physics.ox.ac.uk

d Department of Physics, Soongsil University, Seoul 06978, Korea

e Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea
E-mail: hyunsik7@dongguk.edu

Abstract

Due to its unique layer-number dependent electronic band structure and strong excitonic features, atomically thin MoS2 is an ideal 2D system where intriguing photoexcited-carrier-induced phenomena can be detected in excitonic luminescence. We perform micro-photoluminescence (PL) measurements and observe that the PL peak redshifts nonlinearly in mono- and bi-layer MoS2 as the excitation power is increased. The excited carrier-induced optical bandgap shrinkage is found to be proportional to n4/3, where n is the optically-induced free carrier density. The large exponent value of 4/3 is explicitly distinguished from a typical value of 1/3 in various semiconductor quantum well systems. The peculiar n4/3 dependent optical bandgap redshift may be due to the interplay between bandgap renormalization and reduced exciton binding energy.

Graphical abstract: Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2

About
Cited by
Related
Download options Please wait...

Supplementary files

Article information

DOI
https://doi.org/10.1039/C7NR01834G
Article type
Paper
Submitted
15 Mar 2017
Accepted
04 May 2017
First published
05 May 2017

Nanoscale, 2017,9, 10647-10652

Permissions

Request permissions

Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2

Y. Park, S. W. Han, C. C. S. Chan, B. P. L. Reid, R. A. Taylor, N. Kim, Y. Jo, H. Im and K. S. Kim, Nanoscale, 2017, 9, 10647 DOI: 10.1039/C7NR01834G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements