Abstract

We have studied a wide-bandgap oxide semiconductor, ${\mathrm{CaGa}}_{1.99}{\mathrm{Cr}}_{0.01}{\mathrm{O}}_4$, which possesses high crystal field strength and develops deep traps. These traps efficiently store electric charges after excitation with ultraviolet light. Stimulation of trap charges using infrared radiation (both coherent and incoherent) gives wideband emission of ${\mathrm{Cr}}^{3+}$ in the red–infrared region, which is similar to the photon upconversion process in lanthanides. Under laser excitation, high photon density and local heating pronounce the coupling of ${}^{2}E$ and ${}^4{T}_2$ states and causes an excited state crossover of the population from the ${}^{2}E$ to ${}^4{T}_2$ state. This expands the emission band-width of ${\mathrm{Cr}}^{3+}$ up to 900 nm.

© 2016 Optical Society of America

Phonon-assisted upconversion charging in Zn₃Ga₂GeO₈:Cr³⁺ near-infrared persistent phosphor

Feng Liu, Yafei Chen, Yanjie Liang, and Zhengwei Pan
Opt. Lett. 41(5) 954-957 (2016)

Photostimulation induced persistent luminescence in Y₃Al₂Ga₃O₁₂:Cr³⁺

Yumiko Katayama, Bruno Viana, Didier Gourier, Jian Xu, and Setsuhisa Tanabe
Opt. Mater. Express 6(4) 1405-1413 (2016)

Cr³⁺-doped Bi₂Ga₄O₉-Bi₂Al₄O₉ solid-solution phosphors: crystal-field modulation and lifetime-based temperature sensing

Daqin Chen, Xiao Chen, Xiaoyue Li, Hai Guo, Shen Liu, and Xinyue Li
Opt. Lett. 42(23) 4950-4953 (2017)

Tuning of near-infrared-to-near-infrared luminescence from one-photon to two-photon anti-Stokes shift in Ca₃Ga_{2- x}Cr_xGe₃O₁₂ via varying Cr³⁺ content

Huihong Lin, Ting Yu, Gongxun Bai, Qinyuan Zhang, and Jianhua Hao
Opt. Lett. 42(4) 715-718 (2017)

Detecting the origin of luminescence in Er³⁺-doped hexagonal Na_1.5Gd_1.5F₆ phosphors

Xiangfu Wang, Yanyan Bu, Xiaohong Yan, Peiqing Cai, Jing Wang, Lin Qin, Thiquynh Vu, and Hyo Jin Seo
Opt. Lett. 41(22) 5314-5317 (2016)