1. Origin and Quenching of Novel ultraviolet and blue emission in NdGaO3: Concept of Super-Hydrogenic Dopants
- Author
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Weiming Lü, Zhen Huang, Mallikarjuna Rao Motapothula, Thirumaleshwara Bhatt, Saurav Prakash, Sukant K. Tripathy, Xiaohu Huang, Ariando Ariando, Mark Asta, Thirumalai Venkatesan, Nikolai Yakovlev, Chunxiao Cong, Surani Bin Dolmanan, Zhiqi Liu, Surajit Saha, Soo Jin Chua, Ting Yu, Abhijeet Patra, Siddhartha Ghosh, Chuan Beng Tay, Jianqiang Chen, and Yao Cai
- Subjects
Quenching ,Multidisciplinary ,Photoluminescence ,Materials science ,Dopant ,Doping ,Analytical chemistry ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Article ,Ion ,Other Physical Sciences ,X-ray photoelectron spectroscopy ,0103 physical sciences ,Biochemistry and Cell Biology ,010306 general physics ,0210 nano-technology ,Bohr radius ,Perovskite (structure) - Abstract
In this study we report the existence of novel ultraviolet (UV) and blue emission in rare-earth based perovskite NdGaO3 (NGO) and the systematic quench of the NGO photoluminescence (PL) by Ce doping. Study of room temperature PL was performed in both single-crystal and polycrystalline NGO (substrates and pellets) respectively. Several NGO pellets were prepared with varying Ce concentration and their room temperature PL was studied using 325 nm laser. It was found that the PL intensity shows a systematic quench with increasing Ce concentration. XPS measurements indicated that nearly 50% of Ce atoms are in the 4+ state. The PL quench was attributed to the novel concept of super hydrogenic dopant (SHD)”, where each Ce4+ ion contributes an electron which forms a super hydrogenic atom with an enhanced Bohr radius, due to the large dielectric constant of the host. Based on the critical Ce concentration for complete quenching this SHD radius was estimated to be within a range of 0.85 nm and 1.15 nm whereas the predicted theoretical value of SHD radius for NdGaO3 is ~1.01 nm.
- Published
- 2016