Room-temperature unidirectional routing of valley excitons of monolayer WSe2 via plasmonic near-field interference in symmetric nano-slits
Due to the short valley polarization time, it is hardly to separate opposite valley pseudospin of transition metal dichalcogenides (TMDs) for their practical applications in valleytronics. Coupling TMDs to unidirectional surface plasmon polariton (SPP) can overcome this obstacle. However, it is requ...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
De Gruyter
2023-08-01
|
| Series: | Nanophotonics |
| Subjects: | |
| Online Access: | https://doi.org/10.1515/nanoph-2023-0368 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850063781665701888 |
|---|---|
| author | Wen Xinglin Zhou Yunxi Chen Sijie Yao Wendian Li Dehui |
| author_facet | Wen Xinglin Zhou Yunxi Chen Sijie Yao Wendian Li Dehui |
| author_sort | Wen Xinglin |
| collection | DOAJ |
| description | Due to the short valley polarization time, it is hardly to separate opposite valley pseudospin of transition metal dichalcogenides (TMDs) for their practical applications in valleytronics. Coupling TMDs to unidirectional surface plasmon polariton (SPP) can overcome this obstacle. However, it is required to break the symmetry to induce the asymmetric coupling between valley exciton dipole and SPP to route valley exciton in previously proposed strategies. Herein, by utilizing a new mechanism that near-field interference can create directional SPP in symmetric nanostructures, we realize directional routing of valley exciton emission of monolayer WSe2 at room temperature with a symmetric nano-slits array. The near-field interference enabled directional SPP in our device not only render the exciton diffusion length increase from 0.9 to 3.0 μm, but also lead to a valley exciton separation length of 0.7 μm with degree of valley polarization up to 22 %. This valley excitons separation is attributed to the non-flat WSe2 in the nano-slits region, which makes the exciton dipoles present in-plane and out-of-plane simultaneously. Our work provides a convenient and promising strategy towards room temperature on-chip integrated valleytronic devices. |
| format | Article |
| id | doaj-art-137f4f03bd3e411d8854bdcdc783cf40 |
| institution | DOAJ |
| issn | 2192-8614 |
| language | English |
| publishDate | 2023-08-01 |
| publisher | De Gruyter |
| record_format | Article |
| series | Nanophotonics |
| spelling | doaj-art-137f4f03bd3e411d8854bdcdc783cf402025-08-20T02:49:30ZengDe GruyterNanophotonics2192-86142023-08-0112173529353410.1515/nanoph-2023-0368Room-temperature unidirectional routing of valley excitons of monolayer WSe2 via plasmonic near-field interference in symmetric nano-slitsWen Xinglin0Zhou Yunxi1Chen Sijie2Yao Wendian3Li Dehui4School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan430074, ChinaSchool of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan430074, ChinaSchool of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan430074, ChinaSchool of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan430074, ChinaSchool of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan430074, ChinaDue to the short valley polarization time, it is hardly to separate opposite valley pseudospin of transition metal dichalcogenides (TMDs) for their practical applications in valleytronics. Coupling TMDs to unidirectional surface plasmon polariton (SPP) can overcome this obstacle. However, it is required to break the symmetry to induce the asymmetric coupling between valley exciton dipole and SPP to route valley exciton in previously proposed strategies. Herein, by utilizing a new mechanism that near-field interference can create directional SPP in symmetric nanostructures, we realize directional routing of valley exciton emission of monolayer WSe2 at room temperature with a symmetric nano-slits array. The near-field interference enabled directional SPP in our device not only render the exciton diffusion length increase from 0.9 to 3.0 μm, but also lead to a valley exciton separation length of 0.7 μm with degree of valley polarization up to 22 %. This valley excitons separation is attributed to the non-flat WSe2 in the nano-slits region, which makes the exciton dipoles present in-plane and out-of-plane simultaneously. Our work provides a convenient and promising strategy towards room temperature on-chip integrated valleytronic devices.https://doi.org/10.1515/nanoph-2023-0368near-field interferencetmdsvalley separationvalleytronics |
| spellingShingle | Wen Xinglin Zhou Yunxi Chen Sijie Yao Wendian Li Dehui Room-temperature unidirectional routing of valley excitons of monolayer WSe2 via plasmonic near-field interference in symmetric nano-slits Nanophotonics near-field interference tmds valley separation valleytronics |
| title | Room-temperature unidirectional routing of valley excitons of monolayer WSe2 via plasmonic near-field interference in symmetric nano-slits |
| title_full | Room-temperature unidirectional routing of valley excitons of monolayer WSe2 via plasmonic near-field interference in symmetric nano-slits |
| title_fullStr | Room-temperature unidirectional routing of valley excitons of monolayer WSe2 via plasmonic near-field interference in symmetric nano-slits |
| title_full_unstemmed | Room-temperature unidirectional routing of valley excitons of monolayer WSe2 via plasmonic near-field interference in symmetric nano-slits |
| title_short | Room-temperature unidirectional routing of valley excitons of monolayer WSe2 via plasmonic near-field interference in symmetric nano-slits |
| title_sort | room temperature unidirectional routing of valley excitons of monolayer wse2 via plasmonic near field interference in symmetric nano slits |
| topic | near-field interference tmds valley separation valleytronics |
| url | https://doi.org/10.1515/nanoph-2023-0368 |
| work_keys_str_mv | AT wenxinglin roomtemperatureunidirectionalroutingofvalleyexcitonsofmonolayerwse2viaplasmonicnearfieldinterferenceinsymmetricnanoslits AT zhouyunxi roomtemperatureunidirectionalroutingofvalleyexcitonsofmonolayerwse2viaplasmonicnearfieldinterferenceinsymmetricnanoslits AT chensijie roomtemperatureunidirectionalroutingofvalleyexcitonsofmonolayerwse2viaplasmonicnearfieldinterferenceinsymmetricnanoslits AT yaowendian roomtemperatureunidirectionalroutingofvalleyexcitonsofmonolayerwse2viaplasmonicnearfieldinterferenceinsymmetricnanoslits AT lidehui roomtemperatureunidirectionalroutingofvalleyexcitonsofmonolayerwse2viaplasmonicnearfieldinterferenceinsymmetricnanoslits |