Boyi Zhou, Ran Jing, Wenjun Zheng, Xinzhong Chen, Jiacheng Sun, Zijian Zhou, Heng Wang, Lukas Wehmeier, Erdong Song, Bing Cheng, Yinan Dong, Matthew Cothrine, David Mandrus, G. L. Carr, Xu Du, Erik A. Henriksen, D. N. Basov and Mengkun Liu*,
{"title":"石墨烯/α-RuCl3异质结构中的低损耗电荷转移等离子体","authors":"Boyi Zhou, Ran Jing, Wenjun Zheng, Xinzhong Chen, Jiacheng Sun, Zijian Zhou, Heng Wang, Lukas Wehmeier, Erdong Song, Bing Cheng, Yinan Dong, Matthew Cothrine, David Mandrus, G. L. Carr, Xu Du, Erik A. Henriksen, D. N. Basov and Mengkun Liu*, ","doi":"10.1021/acsphotonics.5c0029610.1021/acsphotonics.5c00296","DOIUrl":null,"url":null,"abstract":"<p >Charge transfer at material interfaces governs a wide range of physical properties, from electronic band structures to emergent collective excitations. In two-dimensional (2D) material heterostructures, charge transfer phenomena play important roles in enabling novel quantum phases, proximity effects, and tunable plasmonic responses. One representative charge transfer interface is formed between α-RuCl<sub>3</sub>, a van der Waals material with high electron affinity, and graphene. Significant charge transfer across this interface induces the formation of charge-transfer plasmon polaritons (CPPs), hybrid excitations between light and charge oscillations. However, previous studies found that as the charge transfer process takes place, α-RuCl<sub>3</sub> becomes lossy, which limits the quality factor of CPPs. Here, we investigate CPPs down to 10 K using a home-built scattering-type scanning near-field optical microscope (<i>s</i>-SNOM) optimized for low-temperature measurements. Our study reveals a dramatic suppression of plasmon loss channels below 40 K, contributing to a significant enhancement in the plasmonic quality factor. This reduction in loss is likely attributed to the blue shift of the correlation-induced Mott gap in α-RuCl<sub>3</sub> with decreasing temperature, along with the reduction of phonon scattering at low temperature. Our results highlight the potential of using <i>s</i>-SNOM and CPPs to study complex 2D interfaces and reveal correlated electron dynamics in the underlying material.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 6","pages":"3082–3090 3082–3090"},"PeriodicalIF":6.7000,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Low-Loss Charge Transfer Plasmons in Graphene/α-RuCl3 Heterostructures Below 40 K\",\"authors\":\"Boyi Zhou, Ran Jing, Wenjun Zheng, Xinzhong Chen, Jiacheng Sun, Zijian Zhou, Heng Wang, Lukas Wehmeier, Erdong Song, Bing Cheng, Yinan Dong, Matthew Cothrine, David Mandrus, G. L. Carr, Xu Du, Erik A. Henriksen, D. N. Basov and Mengkun Liu*, \",\"doi\":\"10.1021/acsphotonics.5c0029610.1021/acsphotonics.5c00296\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >Charge transfer at material interfaces governs a wide range of physical properties, from electronic band structures to emergent collective excitations. In two-dimensional (2D) material heterostructures, charge transfer phenomena play important roles in enabling novel quantum phases, proximity effects, and tunable plasmonic responses. One representative charge transfer interface is formed between α-RuCl<sub>3</sub>, a van der Waals material with high electron affinity, and graphene. Significant charge transfer across this interface induces the formation of charge-transfer plasmon polaritons (CPPs), hybrid excitations between light and charge oscillations. However, previous studies found that as the charge transfer process takes place, α-RuCl<sub>3</sub> becomes lossy, which limits the quality factor of CPPs. Here, we investigate CPPs down to 10 K using a home-built scattering-type scanning near-field optical microscope (<i>s</i>-SNOM) optimized for low-temperature measurements. Our study reveals a dramatic suppression of plasmon loss channels below 40 K, contributing to a significant enhancement in the plasmonic quality factor. This reduction in loss is likely attributed to the blue shift of the correlation-induced Mott gap in α-RuCl<sub>3</sub> with decreasing temperature, along with the reduction of phonon scattering at low temperature. Our results highlight the potential of using <i>s</i>-SNOM and CPPs to study complex 2D interfaces and reveal correlated electron dynamics in the underlying material.</p>\",\"PeriodicalId\":23,\"journal\":{\"name\":\"ACS Photonics\",\"volume\":\"12 6\",\"pages\":\"3082–3090 3082–3090\"},\"PeriodicalIF\":6.7000,\"publicationDate\":\"2025-06-06\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"ACS Photonics\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://pubs.acs.org/doi/10.1021/acsphotonics.5c00296\",\"RegionNum\":1,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MATERIALS SCIENCE, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Photonics","FirstCategoryId":"101","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acsphotonics.5c00296","RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
Low-Loss Charge Transfer Plasmons in Graphene/α-RuCl3 Heterostructures Below 40 K
Charge transfer at material interfaces governs a wide range of physical properties, from electronic band structures to emergent collective excitations. In two-dimensional (2D) material heterostructures, charge transfer phenomena play important roles in enabling novel quantum phases, proximity effects, and tunable plasmonic responses. One representative charge transfer interface is formed between α-RuCl3, a van der Waals material with high electron affinity, and graphene. Significant charge transfer across this interface induces the formation of charge-transfer plasmon polaritons (CPPs), hybrid excitations between light and charge oscillations. However, previous studies found that as the charge transfer process takes place, α-RuCl3 becomes lossy, which limits the quality factor of CPPs. Here, we investigate CPPs down to 10 K using a home-built scattering-type scanning near-field optical microscope (s-SNOM) optimized for low-temperature measurements. Our study reveals a dramatic suppression of plasmon loss channels below 40 K, contributing to a significant enhancement in the plasmonic quality factor. This reduction in loss is likely attributed to the blue shift of the correlation-induced Mott gap in α-RuCl3 with decreasing temperature, along with the reduction of phonon scattering at low temperature. Our results highlight the potential of using s-SNOM and CPPs to study complex 2D interfaces and reveal correlated electron dynamics in the underlying material.
期刊介绍:
Published as soon as accepted and summarized in monthly issues, ACS Photonics will publish Research Articles, Letters, Perspectives, and Reviews, to encompass the full scope of published research in this field.