Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição
Autor(a) principal: | |
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Data de Publicação: | 2022 |
Tipo de documento: | Tese |
Idioma: | por |
Título da fonte: | Repositório Institucional da UFSCAR |
Texto Completo: | https://repositorio.ufscar.br/handle/ufscar/16367 |
Resumo: | Bidimensional (2D) materials are systems of great interest both from the fundamental physical point of view and for possible applications in electronics, optoelectronics and spintronics. In this thesis, the optical properties of monolayers of transition metal dicalcogenetes (TMD) grown by Chemical Vapor Deposition (CVD) and exfoliated were investigated. In particular, we conducted a systematic study of the optical properties of tungsten disulfide (WS2) of large area (of the order of some cm), grown by van der Waals epitaxy on a CVD system. We investigated the optical properties of these samples using macro-photoluminescence and micro-photoluminescence techniques at low temperatures. We observed that the optical emission of these samples is quite unstable in time and that this optical instability depends on the temperature and power of the laser. This effect was associated with photo-induced doping. In addition, we observed thin peaks in the region of lower energy that are promising candidates for the generation of single photons. In general, the results obtained help to gain a greater understanding of the effects of photo-doping dynamics on these systems, which is important for future applications of TMD-based devices. We also investigated biaxial stress effects on a monolayer of molybdenum diselenide (MoSe2)/h-BN prepared by mechanical exfoliation and dry transfer technique. The sample studied has a region with a bubble of the order of 15 micrometers producing a mechanical biaxial tension of up to 1.3% in that region. We investigated the effects of tension using several experimental techniques, such as PL, magneto-PL and second harmonic generation (HGS). The results obtained showed the presence of a non-uniform tension in the sample, as well as a displacement to red in the PL peaks of the exciton and trion, when compared with the region without tension in the sample. A decrease of the trion binding energy and an increase in the g-factor of the trion and exciton in the bubble region were also observed. The results obtained are consistent with calculations of first principles performed in these systems. The results obtained present valuable information on stress effects in the properties of excitons and trions in MoSe2 monolayer and are interesting for the development of devices with controlled mechanical tension based on TMDs. |
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Soares Covre, FelipeGobato, Yara Galvãohttp://lattes.cnpq.br/7558531056409406Matos, Christiano José Santiago deEndereço para acessar este CV: http://lattes.cnpq.br/6843256597783676http://lattes.cnpq.br/0605656438457962e7184e1c-6923-46f4-a31b-a79343c9fce22022-07-08T13:22:40Z2022-07-08T13:22:40Z2022-06-07SOARES COVRE, Felipe. Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição. 2022. Tese (Doutorado em Física) – Universidade Federal de São Carlos, São Carlos, 2022. Disponível em: https://repositorio.ufscar.br/handle/ufscar/16367.https://repositorio.ufscar.br/handle/ufscar/16367Bidimensional (2D) materials are systems of great interest both from the fundamental physical point of view and for possible applications in electronics, optoelectronics and spintronics. In this thesis, the optical properties of monolayers of transition metal dicalcogenetes (TMD) grown by Chemical Vapor Deposition (CVD) and exfoliated were investigated. In particular, we conducted a systematic study of the optical properties of tungsten disulfide (WS2) of large area (of the order of some cm), grown by van der Waals epitaxy on a CVD system. We investigated the optical properties of these samples using macro-photoluminescence and micro-photoluminescence techniques at low temperatures. We observed that the optical emission of these samples is quite unstable in time and that this optical instability depends on the temperature and power of the laser. This effect was associated with photo-induced doping. In addition, we observed thin peaks in the region of lower energy that are promising candidates for the generation of single photons. In general, the results obtained help to gain a greater understanding of the effects of photo-doping dynamics on these systems, which is important for future applications of TMD-based devices. We also investigated biaxial stress effects on a monolayer of molybdenum diselenide (MoSe2)/h-BN prepared by mechanical exfoliation and dry transfer technique. The sample studied has a region with a bubble of the order of 15 micrometers producing a mechanical biaxial tension of up to 1.3% in that region. We investigated the effects of tension using several experimental techniques, such as PL, magneto-PL and second harmonic generation (HGS). The results obtained showed the presence of a non-uniform tension in the sample, as well as a displacement to red in the PL peaks of the exciton and trion, when compared with the region without tension in the sample. A decrease of the trion binding energy and an increase in the g-factor of the trion and exciton in the bubble region were also observed. The results obtained are consistent with calculations of first principles performed in these systems. The results obtained present valuable information on stress effects in the properties of excitons and trions in MoSe2 monolayer and are interesting for the development of devices with controlled mechanical tension based on TMDs.Materiais bidimensionais (2D) são sistemas de grande interesse tanto do ponto de vista física fundamental como para possíveis aplicações em eletrônica, optoeletrônica e spintrônica. Nesta tese, foram investigadas propriedades óticas de monocamadas de dicalcogenetos de metais de transição (TMD) crescidos por Chemical Vapor Deposition (CVD) e esfoliadas. Em particular, realizamos um estudo sistemático das propriedades óticas de monocamadas de dissulfeto de tungstênio (WS2) de área grande (da ordem de alguns cm), crescidos por de epitaxia de van der Waals em um sistema de CVD. Investigamos as propriedades óticas dessas amostras usando as técnicas de macro-fotoluminescência e micro-fotoluminescência (PL) em baixas temperaturas. Observamos que a emissão ótica destas amostras é bastante instável no tempo e que está instabilidade depende da temperatura e potência do laser. Este efeito foi associado a dopagem fotoinduzida. Esse efeito foi usado para identificar diversos complexos excitônicos. Além disso, observamos picos finos na região de menor energia que são promissores para geração de fótons únicos. De forma geral, os resultados obtidos ajudaram a obter uma maior compreensão sobre os efeitos da dinâmica de fotodopagem por laser nesses sistemas, contribuindo assim para futuras aplicações de dispositivos baseados em TMDs. Investigamos também efeitos de tensão biaxial em uma monocamadas de disseleneto de molibdênio (MoSe2)/h-BN preparada por esfoliação mecânica e por técnica de transferência seca. A amostra estudada possui uma região com uma bolha da ordem de 15 micrômetros produzindo uma tensão biaxial mecânica de até 1.3% nessa região. Investigamos os efeitos de tensão utilizando diversas técnicas experimentais, como PL, magneto-PL e geração de segundo harmônico (SHG). Os resultados obtidos evidenciaram a presença de uma tensão não-uniforme na amostra, bem como um deslocamento para o vermelho nos picos de PL do éxciton e tríon, quando comparamos com a região sem tensão na amostra. Foi também observado uma variação na energia de ligação do tríon e um aumento do fator-g do tríon e do éxciton, na região da bolha. Os resultados obtidos são coerentes com cálculos de primeiros princípios realizado nesses sistemas. Os resultados obtidos apresentam informações importantes sobre os efeitos de tensão nas propriedades de éxcitons e tríons em monocamada de MoSe2 e são interessantes para o desenvolvimento de dispositivos com tensão mecânica controlada baseados em TMDs.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)148496/2016-4porUniversidade Federal de São CarlosCâmpus São CarlosPrograma de Pós-Graduação em Física - PPGFUFSCarAttribution-NonCommercial-NoDerivs 3.0 Brazilhttp://creativecommons.org/licenses/by-nc-nd/3.0/br/info:eu-repo/semantics/openAccessWS2MoSe2FotoluminescênciaTMDsPhotoluminescenceCIENCIAS EXATAS E DA TERRA::FISICAPropriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transiçãoOptical and magneto-optical properties of transitional metal dichalcogenides monolayersinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesis60060095c329bf-cc95-483d-b980-ef5b5a94a0a1reponame:Repositório Institucional da UFSCARinstname:Universidade Federal de São Carlos (UFSCAR)instacron:UFSCARCC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; charset=utf-8811https://repositorio.ufscar.br/bitstream/ufscar/16367/4/license_rdfe39d27027a6cc9cb039ad269a5db8e34MD54ORIGINALTese Felipe Soares Covre.pdfTese Felipe Soares Covre.pdfTexto da Teseapplication/pdf5331374https://repositorio.ufscar.br/bitstream/ufscar/16367/1/Tese%20Felipe%20Soares%20Covre.pdffbef88aac61632ff6f0a4a3623260cdbMD51Carta Comprovante.pdfCarta Comprovante.pdfCarta Comprovanteapplication/pdf422362https://repositorio.ufscar.br/bitstream/ufscar/16367/3/Carta%20Comprovante.pdfee2b781da18dba8bbb87a05242013b52MD53TEXTTese Felipe Soares Covre.pdf.txtTese Felipe Soares Covre.pdf.txtExtracted texttext/plain138917https://repositorio.ufscar.br/bitstream/ufscar/16367/5/Tese%20Felipe%20Soares%20Covre.pdf.txt353a89d8a567f372c3d5b3eb1a7c1f25MD55Carta Comprovante.pdf.txtCarta Comprovante.pdf.txtExtracted texttext/plain1402https://repositorio.ufscar.br/bitstream/ufscar/16367/7/Carta%20Comprovante.pdf.txtcc6678f6a7e85d3e1acba7f6fa2b3d56MD57THUMBNAILTese Felipe Soares Covre.pdf.jpgTese Felipe Soares Covre.pdf.jpgIM Thumbnailimage/jpeg7231https://repositorio.ufscar.br/bitstream/ufscar/16367/6/Tese%20Felipe%20Soares%20Covre.pdf.jpg6e3073d177932108aa4f90a68d6680f8MD56Carta Comprovante.pdf.jpgCarta Comprovante.pdf.jpgIM Thumbnailimage/jpeg13518https://repositorio.ufscar.br/bitstream/ufscar/16367/8/Carta%20Comprovante.pdf.jpgecb0c172d564ef6ac727aa35986b0a95MD58ufscar/163672023-09-18 18:32:28.831oai:repositorio.ufscar.br:ufscar/16367Repositório InstitucionalPUBhttps://repositorio.ufscar.br/oai/requestopendoar:43222023-09-18T18:32:28Repositório Institucional da UFSCAR - Universidade Federal de São Carlos (UFSCAR)false |
dc.title.por.fl_str_mv |
Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição |
dc.title.alternative.eng.fl_str_mv |
Optical and magneto-optical properties of transitional metal dichalcogenides monolayers |
title |
Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição |
spellingShingle |
Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição Soares Covre, Felipe WS2 MoSe2 Fotoluminescência TMDs Photoluminescence CIENCIAS EXATAS E DA TERRA::FISICA |
title_short |
Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição |
title_full |
Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição |
title_fullStr |
Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição |
title_full_unstemmed |
Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição |
title_sort |
Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição |
author |
Soares Covre, Felipe |
author_facet |
Soares Covre, Felipe |
author_role |
author |
dc.contributor.authorlattes.por.fl_str_mv |
http://lattes.cnpq.br/0605656438457962 |
dc.contributor.author.fl_str_mv |
Soares Covre, Felipe |
dc.contributor.advisor1.fl_str_mv |
Gobato, Yara Galvão |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/7558531056409406 |
dc.contributor.advisor-co1.fl_str_mv |
Matos, Christiano José Santiago de |
dc.contributor.advisor-co1Lattes.fl_str_mv |
Endereço para acessar este CV: http://lattes.cnpq.br/6843256597783676 |
dc.contributor.authorID.fl_str_mv |
e7184e1c-6923-46f4-a31b-a79343c9fce2 |
contributor_str_mv |
Gobato, Yara Galvão Matos, Christiano José Santiago de |
dc.subject.por.fl_str_mv |
WS2 MoSe2 Fotoluminescência |
topic |
WS2 MoSe2 Fotoluminescência TMDs Photoluminescence CIENCIAS EXATAS E DA TERRA::FISICA |
dc.subject.eng.fl_str_mv |
TMDs Photoluminescence |
dc.subject.cnpq.fl_str_mv |
CIENCIAS EXATAS E DA TERRA::FISICA |
description |
Bidimensional (2D) materials are systems of great interest both from the fundamental physical point of view and for possible applications in electronics, optoelectronics and spintronics. In this thesis, the optical properties of monolayers of transition metal dicalcogenetes (TMD) grown by Chemical Vapor Deposition (CVD) and exfoliated were investigated. In particular, we conducted a systematic study of the optical properties of tungsten disulfide (WS2) of large area (of the order of some cm), grown by van der Waals epitaxy on a CVD system. We investigated the optical properties of these samples using macro-photoluminescence and micro-photoluminescence techniques at low temperatures. We observed that the optical emission of these samples is quite unstable in time and that this optical instability depends on the temperature and power of the laser. This effect was associated with photo-induced doping. In addition, we observed thin peaks in the region of lower energy that are promising candidates for the generation of single photons. In general, the results obtained help to gain a greater understanding of the effects of photo-doping dynamics on these systems, which is important for future applications of TMD-based devices. We also investigated biaxial stress effects on a monolayer of molybdenum diselenide (MoSe2)/h-BN prepared by mechanical exfoliation and dry transfer technique. The sample studied has a region with a bubble of the order of 15 micrometers producing a mechanical biaxial tension of up to 1.3% in that region. We investigated the effects of tension using several experimental techniques, such as PL, magneto-PL and second harmonic generation (HGS). The results obtained showed the presence of a non-uniform tension in the sample, as well as a displacement to red in the PL peaks of the exciton and trion, when compared with the region without tension in the sample. A decrease of the trion binding energy and an increase in the g-factor of the trion and exciton in the bubble region were also observed. The results obtained are consistent with calculations of first principles performed in these systems. The results obtained present valuable information on stress effects in the properties of excitons and trions in MoSe2 monolayer and are interesting for the development of devices with controlled mechanical tension based on TMDs. |
publishDate |
2022 |
dc.date.accessioned.fl_str_mv |
2022-07-08T13:22:40Z |
dc.date.available.fl_str_mv |
2022-07-08T13:22:40Z |
dc.date.issued.fl_str_mv |
2022-06-07 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
format |
doctoralThesis |
status_str |
publishedVersion |
dc.identifier.citation.fl_str_mv |
SOARES COVRE, Felipe. Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição. 2022. Tese (Doutorado em Física) – Universidade Federal de São Carlos, São Carlos, 2022. Disponível em: https://repositorio.ufscar.br/handle/ufscar/16367. |
dc.identifier.uri.fl_str_mv |
https://repositorio.ufscar.br/handle/ufscar/16367 |
identifier_str_mv |
SOARES COVRE, Felipe. Propriedades ópticas e magneto-ópticas de monocamadas de dicalcogenetos de metais de transição. 2022. Tese (Doutorado em Física) – Universidade Federal de São Carlos, São Carlos, 2022. Disponível em: https://repositorio.ufscar.br/handle/ufscar/16367. |
url |
https://repositorio.ufscar.br/handle/ufscar/16367 |
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por |
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600 600 |
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95c329bf-cc95-483d-b980-ef5b5a94a0a1 |
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Attribution-NonCommercial-NoDerivs 3.0 Brazil http://creativecommons.org/licenses/by-nc-nd/3.0/br/ info:eu-repo/semantics/openAccess |
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Attribution-NonCommercial-NoDerivs 3.0 Brazil http://creativecommons.org/licenses/by-nc-nd/3.0/br/ |
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openAccess |
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Universidade Federal de São Carlos Câmpus São Carlos |
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Programa de Pós-Graduação em Física - PPGF |
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UFSCar |
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Universidade Federal de São Carlos Câmpus São Carlos |
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