title: Geometry strategy for engineering the recombination possibility of excitons in nanowires.
abstract: We proposed a geometry strategy to engineer the radiative recombination possibility and thus the lifetime of excitons in nanowires of some photovoltaic semiconductors by using theoretical analysis and first-principles calculations. We demonstrated that the shape can engineer the symmetry of the wave-functions of band-edge states and influence the radiative recombination possibility. The nanowires need to satisfy the following requirements to forbid the radiative recombination possibility of band-edge excitons: (i) wurtzite structure; (ii) pxy-characterized wave-function of VBM state and (iii) C3v-symmetry shape. The geometrical symmetry results in the pxy-characterized C3v-symmetry wave-function of VBM state and leads to forbidden radiative recombination of band-edge excitons. The geometry strategy offers a flexible proposal to prolong the exciton lifetime, leaving optical absorption impregnable.
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. wqzhang@mail.sic.ac.cn.
authors.forename: Youwei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. wqzhang@mail.sic.ac.cn.
authors.forename: Yubo
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
authors.forename: Haiming
authors.initials: H
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. wqzhang@mail.sic.ac.cn.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
authors.forename: Tianquan
authors.initials: T
authors.lastname: Lian
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. wqzhang@mail.sic.ac.cn and Materials Genome Institute, Shanghai University, Shanghai 200444, China.
authors.forename: Wenqing
authors.initials: W
authors.lastname: Zhang