0000000000891177
AUTHOR
Mitch M.c. Chou
Anisotropic photoluminescence of nonpolar ZnO epilayers and ZnO/Zn1 −xMgxO multiple quantum wells grown on LiGaO2 substrate
Ministry of Science and Technology, Taiwan (104-2221-E-110-012-MY3, 107-2221-E-110-004-MY3); National Natural Science Foundation of China (51602309, U1605245).
Comparison of Luminescence in LiGaO2, Al2 O3 -Ga and Al2 O3 -Li Crystals
We have studied luminescence of LiGaO 2 , Al 2 O 3 -Ga and Al 2 O 3 -Li crystals in order to reveal the nature of luminescence centres and mechanisms in these crystals. In Al 2 O 3 -Ga presence of Ga impurities determines occurrence of the 280 nm emission band, which demonstrates intra-centre character in photoluminescence and recombination character under X-ray irradiation. In Al 2 O 3 -Li crystal lithium induced luminescence is presented with the 326 nm band, which has a recombination character. Basing on spectral similarity of the main luminescence bands in pure LiGaO 2 crystal with the dopant-induced emission bands in Al 2 O 3 , and on peculiarities of the X-ray induced thermoluminescen…
Luminescence properties of LiGaO2 crystal
The study was supported by the Latvia-Lithuania-Taiwan research project “Nonpolar ZnO thin films: growth-related structural and optical properties” (Latvia: LV-LT-TW/2016/5 , Lithuania: TAP LLT 02/2014 , Taiwan: MOST 103-2923-M-110-001-MY3 ).
Optical properties of lithium gallium oxide
Abstract The optical dielectric function tensor of orthorhombic single-crystal LiGaO 2 was determined for polarizations along a , b , and c crystal-axis in the photon energy range from 0.04 eV to 6.5 eV by the generalized spectroscopic ellipsometry. In the far-infrared spectral range from 12.4 meV to 40 meV, the dielectric function was determined from conventional polarized transmittance and polarized reflectance measurements. Lineshape analysis of the dielectric function tensor major components allowed for a determination of the long-wavelength optical phonon characteristics, refractive indices dispersion, and parameters of interband and excitonic optical transitions.
Spectral and kinetic characteristics of pyroelectric luminescence in LiGaO2
Abstract Pyroelectric luminescence was observed in noncentrosymmetrical crystal LiGaO2 with the direct band gap around 6 eV. For the first time spectral and kinetic characteristics of pyroelectric luminescence were obtained. The temporal structure of the PEL signal was determined as a sequence of pulses with duration not longer than several nanoseconds. This allowed proposing of the luminescence mechanism: in vacuum conditions in LiGaO2 crystal pyroelectric luminescence occurs inside the sample due to radiative recombination of electrons with the positively charged intrinsic luminescence centres.