An efficient dual-wavelength laser-diode-pumped Nd:YAG ceramic laser operating at 1112 and 1116 nm is demonstrated.We obtain a maximum total output power of 3.43 W including a 1.77 W 1112 nm component and a 1.66 W 111...An efficient dual-wavelength laser-diode-pumped Nd:YAG ceramic laser operating at 1112 and 1116 nm is demonstrated.We obtain a maximum total output power of 3.43 W including a 1.77 W 1112 nm component and a 1.66 W 1116 nm component under a pump power of 16.1 W,corresponding to a slope efficiency of 23.7%and a total optical-to-optical efficiency of 21.3%.展开更多
A three-sidewalls-prism holographic method has been provided for the fabrication of 3-D fcc-type polymeric photonic crystal using negative photoresist. Special fabrication treatment has been introduced to ensure the s...A three-sidewalls-prism holographic method has been provided for the fabrication of 3-D fcc-type polymeric photonic crystal using negative photoresist. Special fabrication treatment has been introduced to ensure the stability of the fabricated nanostructures. The scanning electronic microscopy (SEM) and the diffraction results testified the good dependability of the fabricated structures. The simulation of the partial band structure is in good agreement with the transmission and reflection spectra obtained by Fourier transform infrared spectroscopy.展开更多
A method to extract phase shifts and reconstruct the object wave in generalized phase-shifting interferometry(GPSI)is proposed.The phase distribution of a standard phase object and the least-square method are used to ...A method to extract phase shifts and reconstruct the object wave in generalized phase-shifting interferometry(GPSI)is proposed.The phase distribution of a standard phase object and the least-square method are used to extract phase shifts over a wide range from 0 to𝜌π.Consequently,the tested object wave can be further reconstructed with the extracted phase shifts.It is accurate and applicable for GPSI of any frame number𝑂(N𝑂≥2).Computer simulation has verified its feasibility and validity.展开更多
The low internal quantum efficiency(IQE)of AlGaN-based deep ultraviolet light emitting diode(DUV-LED)limits its wider application.The main reasons for low IQE include low carrier concentration,poor carrier location an...The low internal quantum efficiency(IQE)of AlGaN-based deep ultraviolet light emitting diode(DUV-LED)limits its wider application.The main reasons for low IQE include low carrier concentration,poor carrier location and large defects.The bending of energy band between AlGaN electron blocking layer and conduction layer obstructs transport of holes to multiple quantum wells.In this paper,we propose a gradual Al-composition p-type AlGaN(p-AlGaN)conduction layer to improve the light emitting properties of AlGaN-based DUV-LED.Increased carrier concentration in the active region enhances the effective radiative recombination rate of the LED.Consequently,the IQE of our optimazited DUV-LED is increased by 162%in comparison with conventional DUV-LEDs.展开更多
基金Supported by the Fund of Key Laboratory of Crystal Material of Shandong University under Grant No KF1101the Fund of Shandong University under Grant No 11170072613176.
文摘An efficient dual-wavelength laser-diode-pumped Nd:YAG ceramic laser operating at 1112 and 1116 nm is demonstrated.We obtain a maximum total output power of 3.43 W including a 1.77 W 1112 nm component and a 1.66 W 1116 nm component under a pump power of 16.1 W,corresponding to a slope efficiency of 23.7%and a total optical-to-optical efficiency of 21.3%.
基金the National Natural Science Foundation of China (Grant Nos 60677027 and 69978009)
文摘A three-sidewalls-prism holographic method has been provided for the fabrication of 3-D fcc-type polymeric photonic crystal using negative photoresist. Special fabrication treatment has been introduced to ensure the stability of the fabricated nanostructures. The scanning electronic microscopy (SEM) and the diffraction results testified the good dependability of the fabricated structures. The simulation of the partial band structure is in good agreement with the transmission and reflection spectra obtained by Fourier transform infrared spectroscopy.
基金Supported by the National Natural Science Foundation of China under Grant No 61275014the Science and Technology Program of Shandong Province under Grant No 2011GGH20119the Natural Science Foundation of Shandong Province under Grant No ZR2011FQ011.
文摘A method to extract phase shifts and reconstruct the object wave in generalized phase-shifting interferometry(GPSI)is proposed.The phase distribution of a standard phase object and the least-square method are used to extract phase shifts over a wide range from 0 to𝜌π.Consequently,the tested object wave can be further reconstructed with the extracted phase shifts.It is accurate and applicable for GPSI of any frame number𝑂(N𝑂≥2).Computer simulation has verified its feasibility and validity.
基金supported by the Key Research and Development Program of Shandong Province(Nos.2018GGX101027,2017GGX201002 and 2016GGX4101)the Union Funds of Guizhou Science and Technology Department and Guizhou Minzu University China(No.LH20157221)+1 种基金the Yantai“13th Five-Year”Marine Economic Innovation and Development Demonstration City Project(No.YHCXZB-L-201703)Fundamental Research Funds of Shandong University in China(Nos.2018WLJH87,2018JCG01 and 2017TB0021)。
文摘The low internal quantum efficiency(IQE)of AlGaN-based deep ultraviolet light emitting diode(DUV-LED)limits its wider application.The main reasons for low IQE include low carrier concentration,poor carrier location and large defects.The bending of energy band between AlGaN electron blocking layer and conduction layer obstructs transport of holes to multiple quantum wells.In this paper,we propose a gradual Al-composition p-type AlGaN(p-AlGaN)conduction layer to improve the light emitting properties of AlGaN-based DUV-LED.Increased carrier concentration in the active region enhances the effective radiative recombination rate of the LED.Consequently,the IQE of our optimazited DUV-LED is increased by 162%in comparison with conventional DUV-LEDs.
