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A kind of glass-in-LuAG (GIP) ceramic with excellent luminous efficiency and high thermal stability was fabricated by solid-state sintering for laser diode (LD)-pumped green-emitting phosphor. The GIP ceramic employing particularly designed borosilicate glass as adhesive exhibits high thermal conductivity (2.8  W/m·K at 80°C) and remarkable improvement in thermal stability (T=711°C) and reliability (luminous flux has only a 0.5% drop after 100 h at 300°C). When the GIP ceramic is pumped by 455 nm blue LDs (14.5  W/mm), a luminous efficacy of 205 lm/W was achieved. More importantly, the GIP ceramic did not have luminescence saturation even under a higher power density (17.1  W/mm) excitation. The novel GIP ceramic, possessing good optical and thermal properties, is promising for LD-pumped green-emitting phosphor.

Saturated electroluminescence behavior was observed in single ZnO micro/nanowire and GaN film heterojunctions fabricated by transferring an individual ZnO micro/nanowire onto p-type GaN substrate. A strong blue emission of ∼460 nm was observed, as a result of interfacial radiative recombination of electrons from n-ZnO and holes from p-GaN. Light-output-current characteristic followed a power law of L ∼ Im, which revealed a superlinear dependence at low current (m = 1.16) and became sublinear (m = 0.72) at high current. According to theoretical analysis, the saturated electroluminescence at high current could be attributed to the saturation of nonradiative recombination and the limitation of electrical-to-optical conversion efficiency.

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In this article, Co/Mn-codoped ZnO nanowires (NWs) were successfully synthesized on a silicon substrate by the thermal evaporation method with Au catalyst. The X-ray diffraction pattern indicated that the Co/Mn-codoped ZnO NWs are a hexagonal wurtzite structure without a second phase, and energy dispersive X-ray spectroscopy revealed that the Co and Mn ions were introduced into the ZnO NWs with the content of ∼0.8 at% and ∼1.2 at%, respectively. Photoluminescence spectra and Raman spectra showed that the Co/Mn were doped into the NWs and resulted in the shift of the near-band-edge emission. Moreover, the novel Raman peak at 519.3 cm(-1) has suggested that the two kinds of cations via doping could affect the local polarizability. Compared with the undoped ZnO NW, the electrical measurement showed that the Co/Mn-codoping enhanced the conductivity by an order of magnitude due to the presence of Co, Mn cations. The electron mobility and carrier concentration of a fabricated field effect transistor (FET) device is 679 cm2 V(-1) s(-1) and 2×10(18) cm(-3), respectively. Furthermore, the M-H curve demonstrated that the Co/Mn-codoped ZnO NWs have obvious ferromagnetic characteristics at room temperature. Our study enhances the understanding of the novel performances of transition-metal codoped ZnO NWs and also provides a potential way to fabricate optoelectronic devices.

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