Selective enriching of trionic emission in a WS_(2)-ZnO hybrid through type-Ⅱband alignment  

作　　者：Jin Feng LEONG Kim Yong LIM Xiao WU Qinghua XU Chorng Haur SOW Eng Tuan POH 

机构地区：[1]Department of Physics,National University of Singapore,Singapore,117551,Singapore [2]Department of Chemistry,National University of Singapore,Singapore,117543,Singapore

出　　处：《Science China(Information Sciences)》2023年第6期59-66,共8页中国科学（信息科学）（英文版）

基　　金：supported by NRF-NUS Resilience and Growth Postdoctoral Fellowship (Grant No.R-144-000-471-281)。

摘　　要：Strategies to modulate the exciton dynamics in ultrathin two-dimensional(2D)semiconductors have always been an integral component in the bid towards improved optoelectronics and quantum photonic devices.The capability to non-destructively tune the relaxation dynamics,valley polarization,binding energies,and population ratio of various excitonic species has been well-sought for advanced applications.Through the rationale design of a WS_(2)-ZnO hybrid platform,we present a distinct increment in the trion-toexciton ratio for WS_(2)emission across a patterned heterostructure.The shift in dominant excitonic species arose due to the efficient charge segregation at the spatially confined interface of the type-Ⅱheterostructure.Owing to the charge transfer process,the resultant emission profile presents up to four times amplification in the trion-to-exciton ratio,with temperature variable trion binding energies up to 59 meV.Since trions possess non-zero charge and spin degrees of freedom,the provision of a higher density of trions with increased binding stability would encourage new opportunities for reproducible optoelectronics and quantum emitters.

关 键 词：HETEROSTRUCTURE TRIONS type-II band alignment 

分 类 号：TB34[一般工业技术—材料科学与工程] TN305[电子电信—物理电子学]