में बचाया:
| मुख्य लेखकों: | , , , , , , , , , |
|---|---|
| स्वरूप: | Preprint |
| प्रकाशित: |
2024
|
| विषय: | |
| ऑनलाइन पहुंच: | https://arxiv.org/abs/2407.04508 |
| टैग: |
टैग जोड़ें
कोई टैग नहीं, इस रिकॉर्ड को टैग करने वाले पहले व्यक्ति बनें!
|
| _version_ | 1866914859607654400 |
|---|---|
| author | Bobzien, Laric Allerbeck, Jonas Krane, Nils Ortega-Guerrero, Andres Wang, Zihao Figueroa, Daniel E. Cintron Dong, Chengye Pignedoli, Carlo A. Robinson, Joshua A. Schuler, Bruno |
| author_facet | Bobzien, Laric Allerbeck, Jonas Krane, Nils Ortega-Guerrero, Andres Wang, Zihao Figueroa, Daniel E. Cintron Dong, Chengye Pignedoli, Carlo A. Robinson, Joshua A. Schuler, Bruno |
| contents | Defect engineering in two-dimensional semiconductors has been exploited to tune the optoelectronic properties and introduce new quantum states in the band gap. Chalcogen vacancies in transition metal dichalcogenides in particular have been found to strongly impact charge carrier concentration and mobility in 2D transistors as well as feature sub-gap emission and single-photon response. In this letter, we investigate the layer-dependent charge state lifetime of Se vacancies in WSe$_2$. In one monolayer WSe$_2$, we observe ultrafast charge transfer from the lowest unoccupied orbital of the top Se vacancy to the graphene substrate within (1.0 $\pm$ 0.2) ps measured via the current saturation in scanning tunneling approach curves. For Se vacancies decoupled by TMD multilayers, we find a sub-exponential increase of the charge lifetime from (62 $\pm$ 14) ps in bilayer to few nanoseconds in four-layer WSe$_2$, alongside a reduction of the defect state binding energy. Additionally, we attribute the continuous suppression and energy shift of the dI/dV in-gap defect state resonances at very close tip--sample distances to a current saturation effect. Our results provide a key measure of the layer-dependent charge transfer rate of chalcogen vacancies in TMDs. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2407_04508 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Layer-Dependent Charge State Lifetime of Single Se Vacancies in WSe$_2$ Bobzien, Laric Allerbeck, Jonas Krane, Nils Ortega-Guerrero, Andres Wang, Zihao Figueroa, Daniel E. Cintron Dong, Chengye Pignedoli, Carlo A. Robinson, Joshua A. Schuler, Bruno Mesoscale and Nanoscale Physics Materials Science Defect engineering in two-dimensional semiconductors has been exploited to tune the optoelectronic properties and introduce new quantum states in the band gap. Chalcogen vacancies in transition metal dichalcogenides in particular have been found to strongly impact charge carrier concentration and mobility in 2D transistors as well as feature sub-gap emission and single-photon response. In this letter, we investigate the layer-dependent charge state lifetime of Se vacancies in WSe$_2$. In one monolayer WSe$_2$, we observe ultrafast charge transfer from the lowest unoccupied orbital of the top Se vacancy to the graphene substrate within (1.0 $\pm$ 0.2) ps measured via the current saturation in scanning tunneling approach curves. For Se vacancies decoupled by TMD multilayers, we find a sub-exponential increase of the charge lifetime from (62 $\pm$ 14) ps in bilayer to few nanoseconds in four-layer WSe$_2$, alongside a reduction of the defect state binding energy. Additionally, we attribute the continuous suppression and energy shift of the dI/dV in-gap defect state resonances at very close tip--sample distances to a current saturation effect. Our results provide a key measure of the layer-dependent charge transfer rate of chalcogen vacancies in TMDs. |
| title | Layer-Dependent Charge State Lifetime of Single Se Vacancies in WSe$_2$ |
| topic | Mesoscale and Nanoscale Physics Materials Science |
| url | https://arxiv.org/abs/2407.04508 |