A deep UV light photodetector is assembled by coating multilayer graphene on beta-gallium oxide (β-Ga O ) wafer. Optoelectronic analysis reveals that the heterojunction device is virtually blind to light illumination with wavelength longer than 280 nm, but is highly sensitive to 254 nm light with very good stability and reproducibility.

Nanophosphors of normalY3Al5normalO12∕Ce3+ (YAG/Ce) were synthesized with a novel salted sol-gel (SSG) method in which a water solution of inorganic salt, yttrium nitrate [ Y(NnormalO3)3 , YNO], was used with a traditional metal alkoxide precursor, aluminum sec-butoxide [ Al(OnormalC4normalH9)3 , ASB], in sol-gel synthesis. With the SSG method, a YAG single phase could be obtained by sintering the dry gel of normalAl2normalO3 and normalY2normalO3 mixture for 2h at 800°C . The YAG particle size was in a range from 30to100nm . Luminescence properties of the YAG samples with different Ce3+ doping concentrations were studied. The peak intensity of luminescence was found at 4% Ce3+ doping concentration. Red shift of the emission peaks was observed when the doping concentration was increased.

We report on a simple passivation strategy to improve the device performance of a near infrared (NIR) photodetector. Optoelectronic analysis reveals that after ultrathin AlOxpassivation, the device exhibits an obvious increase in on/off ratio. What is more, the response speed of the device was improved by more than 100 times, from 48 μs to 380 ns.

Light manipulation is paramountly important to the fabrication of high‐performance optoelectronic devices such as solar cells and photodetectors. In this study, a high‐performance near‐infrared light nanophotodetector (NIRPD) was fabricated based on a germanium nanoneedles array (GeNNs array) with strong light confining capability, and single‐layer graphene (SLG) modified with heavily doped indium tin oxide nanoparticles (ITONPs), which were capable of inducing localized surface plasmon resonance (LSPR) under NIR irradiation. An optoelectronic study shows that after modification with ITONPs the device performance including photocurrent, responsivity and detectivity was considerably improved. In addition, the ITONPs@SLG/GeNNs array NIRPD was able to monitor fast‐switching optical signals, the frequency was as high as 1 MHz, with very fast response rates. Theoretical simulations based on finite‐element method (FEM) revealed that the observed high performance was not only due to the strong light‐confining capability of the GeNNs array, but also due to the plasmonic ITONPs‐induced hot electron injection. The above results suggest that the present NIRPD will have great potential in future optoelectronic devices application.