Electrically Tunable and Dramatically Enhanced Valley-Polarized Emission of Monolayer WSâ‚‚ at Room Temperature with Plasmonic Archimedes Spiral Nanostructures
In: Advanced Materials, 34(3), Art. No. 2104863, (2022-01-20, 2022
academicJournal
Zugriff:
Monolayer transition metal dichalcogenides (TMDs) have intrinsic valley degrees of freedom, making them appealing for exploiting valleytronic applications in information storage and processing. WS₂ monolayer possesses two inequivalent valleys in the Brillouin zone, each valley coupling selectively with a circular polarization of light. The degree of valley polarization (DVP) under the excitation of circularly polarized light (CPL) is a parameter that determines the purity of valley polarized photoluminescence (PL) of monolayer WS₂. Here efficient tailoring of valley-polarized PL from monolayer WS₂ at room temperature (RT) through surface plasmon–exciton interactions with plasmonic Archimedes spiral (PAS) nanostructures is reported. The DVP of WS₂ at RT can be enhanced from <5% to 40% and 50% by using 2 turns (2T) and 4 turns (4T) of PAS, respectively. Further enhancement and control of excitonic valley polarization is demonstrated by electrostatically doping monolayer WS₂. For CPL on WS₂–2TPAS heterostructures, the 40% valley polarization is enhanced to 70% by modulating the carrier doping via a backgate, which may be attributed to the screening of momentum-dependent long-range electron–hole exchange interactions. The manifestation of electrically tunable valley-polarized emission from WS₂–PAS heterostructures presents a new strategy toward harnessing valley excitons for application in ultrathin valleytronic devices. ; © 2021 Wiley-VCH GmbH. Issue Online: 21 January 2022; Version of Record online: 28 November 2021; Accepted manuscript online: 01 November 2021; Manuscript revised: 03 October 2021; Manuscript received: 25 June 2021. This work was jointly supported by the Army Research Office under the Multi-University Research Initiative (MURI) program (award #W911NF-16-1-0472) and the National Science Foundation under the Physics Frontier Center program for Institute for Quantum Information and Matter (IQIM) at the California Institute of Technology (award #1733907). The authors are also ...
Titel: |
Electrically Tunable and Dramatically Enhanced Valley-Polarized Emission of Monolayer WSâ‚‚ at Room Temperature with Plasmonic Archimedes Spiral Nanostructures
|
---|---|
Autor/in / Beteiligte Person: | Lin, Weiâ€Hsiang ; Wu, Pin Chieh ; Akbari, Hamidreza ; Rossman, George R. ; Yeh, Nai-Chang ; Atwater, Harry A. |
Link: | |
Zeitschrift: | Advanced Materials, 34(3), Art. No. 2104863, (2022-01-20, 2022 |
Veröffentlichung: | Wiley, 2022 |
Medientyp: | academicJournal |
DOI: | 10.1002/adma.202104863 |
Schlagwort: |
|
Sonstiges: |
|