Abstract
In van der Waals (vdW) heterostructures, the interlayer electron-phonon coupling (EPC) provides one unique channel to nonlocally engineer these elementary particles. However, limited by the stringent occurrence conditions, the efficient engineering of interlayer EPC remains elusive. Here we report a multitier engineering of interlayer EPC in WS2/boron nitride (BN) heterostructures, including isotope enrichments of BN substrates, temperature, and high-pressure tuning. The hyperfine isotope dependence of Raman intensities was unambiguously revealed. In combination with theoretical calculations, we anticipate that WS2/BN supercells could induce Brillouin-zone-folded phonons that contribute to the interlayer coupling, leading to a complex nature of broad Raman peaks. We further demonstrate the significance of a previously unexplored parameter, the interlayer spacing. By varying the temperature and high pressure, we effectively manipulated the strengths of EPC with on/off capabilities, indicating critical thresholds of the layer-layer spacing for activating and strengthening interlayer EPC. Our findings provide new opportunities to engineer vdW heterostructures with controlled interlayer coupling.
Original language | English |
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Pages (from-to) | 2725-2733 |
Number of pages | 9 |
Journal | Nano Letters |
Volume | 22 |
Issue number | 7 |
DOIs | |
State | Published - Apr 13 2022 |
Funding
This work was supported by the National Natural Science Foundation of China (Project Nos. U1932153, 11974001, 11934003, 52025023, 51991342, 11888101, 52125307, 52021006), the National Key R&D Program of China (2019YFA0307800, 2021YFA1400500), the Beijing Natural Science Foundation (Z190011), the Key Research Program of Frontier Sciences, CAS (QYZDB-SSW-JSC019), and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB28000000). We acknowledge the Electron Microscopy Laboratory at Peking University for the use of an electron microscope. L.L. acknowledges work at the Center for Nanophase Materials Sciences, which is a U.S. Department of Energy Office of Science User Facility.
Funders | Funder number |
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Center for Nanophase Materials Sciences | |
Key Research Program of Frontier Sciences, CAS | QYZDB-SSW-JSC019 |
U.S. Department of Energy | |
National Natural Science Foundation of China | 51991342, 52021006, 11888101, 11974001, 52025023, U1932153, 11934003, 52125307 |
Chinese Academy of Sciences | XDB28000000 |
Natural Science Foundation of Beijing Municipality | Z190011 |
National Key Research and Development Program of China | 2021YFA1400500, 2019YFA0307800 |
Keywords
- electron-phonon coupling
- high-pressure engineering
- interlayer spacing
- isotope engineering
- vdW heterostructure