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Abstract Plasmonic hot‐electron‐assisted control of emission intensities and dynamics of CdSe/ZnS and infrared PbS quantum dots are studied. This is done by exploring the impact of Au/Si and Ag/Si Schottky junctions on the decay rates of such quantum dots when these junctions are placed in close vicinity of a Si/Al oxide charge barrier, forming metal‐oxide plasmonic metafilms. Such structures are used to investigate how metal‐dependent distributions of hot electrons and their capture via Schottky junctions can lead to suppression of the defect environments of quantum dots, offering a novel platform wherein off‐resonant (non‐Purcell) plasmonic processes are used to control exciton dynamics. These results show that Ag metafilms can enhance the emission of CdSe/ZnS quantum dots and elongate their lifetimes more than Au metafilms. This highlights the more efficient nature of Ag/Si Schottky junctions for hot electron excitation and capture. These results also show that such junctions can significantly suppress the nonradiative decay rates of PbS quantum dots at frequencies far from the plasmon resonances. These results demonstrate a field‐effect passivation of quantum dot defects via entrapment of hot electrons and control of emission intensities and dynamics of quantum dots via the nearly frequency‐independent electrostatic field of such electrons.
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This content will become publicly available on April 14, 2026
Schottky barrier formation and band realignment of rare-earth tritelluride charge density wave material–semiconductor interfaces
We investigated the formation of Schottky barriers at the interface between rare-earth tritelluride (RTe3) crystals and n-type silicon (n-Si) substrates. This study explores the rectifying characteristics of RTe3/n-Si junctions (R = Dy, Ho, Er) and their relation to the charge density wave (CDW) transition. Using the thermionic emission model, we analyzed current–voltage (I–V) measurements to obtain the Schottky barrier height (ϕSBH) and the ideality factor (η). The temperature dependence of the extracted ϕSBH and η reveals kink features near the CDW transition temperature. The Schottky–Mott model is employed to explain these kink features in the derivatives of ϕSBH and 1/η and attributes them to changes in the work function of RTe3 during the CDW transition. Our findings suggest that Schottky junctions can be utilized to probe the electronic states of RTe3, enabling potential RTe3 device applications in electronics and optoelectronics.
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- PAR ID:
- 10587182
- Publisher / Repository:
- Applied Physics Letters
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 126
- Issue:
- 15
- ISSN:
- 0003-6951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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