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Updated: Dec 8, 2025

Synthesis of Hierarchical ZnO/CdSSe Heterostructure Nanotrees
Published on: November 29, 2016
Strain gradient induced spatially indirect excitons in single crystalline ZnO nanowires
Zhao Liu1, Xuewen Fu2, Dong-Bo Zhang3
1Beijing Computational Science Research Center, Beijing 100193, China. dbzhang@bnu.edu.cn.
Abstract:
Spatially indirect excitons are important not only for the exploration of intriguing many-body effects but also for the development of applications such as solar cells with high efficiency. This type of exciton usually exists in heterostructures. Using the generalized Bloch theorem coupled with the density-functional tight-binding method, we reveal that spatially indirect excitons may emerge in single crystalline ZnO nanowires under bending. The underlying mechanism is attributed to the formation of an effective type-II band alignment due to the strain-gradient of the bent nanowires. Our finding paves a new route to realize spatially indirect excitons by strain engineering.
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