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Enhancement of silicon modulating properties in the THz range by YAG-Ce coating.

ABSTRACT: Y3Al5-xGaxO12:Ce3+,V3+ (YAG:Ce) has excellent chemical stability and unprecedented luminous efficiency. Its strong photoresponsive property is thoroughly utilized in designing excellent optical information storage device. Here, the remarkable photoconductivity of YAG:Ce is exploited to demonstrate a hybrid YAG:Ce-silicon device that shows high speed terahertz wave spatial modulation. A wide terahertz spectra modulation is observed under different pump powers in frequency range from 0.2 to 1.8 THz. Furthermore, a dynamic control of the terahertz wave intensity is also observed in the transmission system. The modulation speed and depth of the device is measured to be 4 MHz (vs 0.2 kHz)and 83.8%(vs50%) for bare silicon, respectively. The terahertz transmission spectra exhibits highly efficiency terahertz modulation by optically pumping a YAG:Ce film on silicon with low optical pump fluence.

SUBMITTER: Li JS

PROVIDER: S-EPMC7171083 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Enhancement of silicon modulating properties in the THz range by YAG-Ce coating.

Li Jiu-Sheng JS Hu Mu-Shu MS

Scientific reports 20200420 1

Y3Al5-xGaxO12:Ce3+,V3+ (YAG:Ce) has excellent chemical stability and unprecedented luminous efficiency. Its strong photoresponsive property is thoroughly utilized in designing excellent optical information storage device. Here, the remarkable photoconductivity of YAG:Ce is exploited to demonstrate a hybrid YAG:Ce-silicon device that shows high speed terahertz wave spatial modulation. A wide terahertz spectra modulation is observed ...[more]

PMID: 32313115

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