Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2
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 obs...
Main Authors: | , , , , , , , , |
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Format: | Journal article |
Language: | English |
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Royal Society of Chemistry
2017
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_version_ | 1797093704973942784 |
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author | Park, Y Han, S Chan, C Reid, B Taylor, R Kim, N Jo, Y Im, H Kim, K |
author_facet | Park, Y Han, S Chan, C Reid, B Taylor, R Kim, N Jo, Y Im, H Kim, K |
author_sort | Park, Y |
collection | OXFORD |
description | 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. |
first_indexed | 2024-03-07T04:04:09Z |
format | Journal article |
id | oxford-uuid:c5915c15-0096-4fc0-a5e8-3d3635ffca0d |
institution | University of Oxford |
language | English |
last_indexed | 2024-03-07T04:04:09Z |
publishDate | 2017 |
publisher | Royal Society of Chemistry |
record_format | dspace |
spelling | oxford-uuid:c5915c15-0096-4fc0-a5e8-3d3635ffca0d2022-03-27T06:31:59ZInterplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:c5915c15-0096-4fc0-a5e8-3d3635ffca0dEnglishSymplectic Elements at OxfordRoyal Society of Chemistry2017Park, YHan, SChan, CReid, BTaylor, RKim, NJo, YIm, HKim, KDue 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. |
spellingShingle | Park, Y Han, S Chan, C Reid, B Taylor, R Kim, N Jo, Y Im, H Kim, K Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2 |
title | Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2 |
title_full | Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2 |
title_fullStr | Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2 |
title_full_unstemmed | Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2 |
title_short | Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2 |
title_sort | interplay between many body effects and coulomb screening in the optical bandgap of atomically thin mos2 |
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