In this study, the V-I transmission matrix formalism （V-I method） is proposed to analyze the spectrum characteristics of the uniform fiber Bragg grating （FBG）-based acousto--opfic modulators （UFBG-AOM）. The simu...In this study, the V-I transmission matrix formalism （V-I method） is proposed to analyze the spectrum characteristics of the uniform fiber Bragg grating （FBG）-based acousto--opfic modulators （UFBG-AOM）. The simulation results demon- strate that both the amplitude of the acoustically induced strain and the frequency of the acoustic wave （AW） have an effect on the spectrum. Additionally, the wavelength spacing between the primary reflectivity peak and the secondary reflectivity peak is proportional to the acoustic frequency with the ratio 0.1425 nm/MHz. Meanwhile, we compare the amount of calculation. For the FBG whose period is M, the calculation of the V-I method is 4 × （2M-l） in addition/subtraction, 8 × （2M - 1） in multiply/division and 2M in exponent arithmetic, which is almost a quarter of the multi-film method and transfer matrix （TM） method. The detailed analysis indicates that, compared with the conventional multi-film method and transfer matrix （TM） method, the V-I method is faster and less complex.展开更多
Perovskite nanostructured films are essential to create advanced optoelectronic and photovoltaic devices because of the additional degrees of freedom of manipulation by light reflection and structural colouration,as w...Perovskite nanostructured films are essential to create advanced optoelectronic and photovoltaic devices because of the additional degrees of freedom of manipulation by light reflection and structural colouration,as well as by light trapping and localisation,resulting in control of intensity or polarisation of luminescence.In this paper,we report structural colouration and photoluminescence anisotropy in perovskite films deposited on a substrate with laser-induced periodic surface structures(LIPSSs)on a thin TiO_(2)layer.The LIPSS TiO_(2)layer improves charge extraction from the perovskite films,confirmed by a time-resolved photoluminescence analysis.The developed method of substrate nanostructuring does not damage the perovskite films,in contrast to direct laser ablation,imprinting by a mould,mechanical scratching with a cantilever,or plasma-chemical etching.Moreover,the LIPSS formation is appropriate for upscaling owing to the high speed of LIPSS writing(2.25 cm^(2)min^(-1))and uniform surface nanostructuring.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61275076)
文摘In this study, the V-I transmission matrix formalism （V-I method） is proposed to analyze the spectrum characteristics of the uniform fiber Bragg grating （FBG）-based acousto--opfic modulators （UFBG-AOM）. The simulation results demon- strate that both the amplitude of the acoustically induced strain and the frequency of the acoustic wave （AW） have an effect on the spectrum. Additionally, the wavelength spacing between the primary reflectivity peak and the secondary reflectivity peak is proportional to the acoustic frequency with the ratio 0.1425 nm/MHz. Meanwhile, we compare the amount of calculation. For the FBG whose period is M, the calculation of the V-I method is 4 × （2M-l） in addition/subtraction, 8 × （2M - 1） in multiply/division and 2M in exponent arithmetic, which is almost a quarter of the multi-film method and transfer matrix （TM） method. The detailed analysis indicates that, compared with the conventional multi-film method and transfer matrix （TM） method, the V-I method is faster and less complex.
基金the Interdisciplinary Resource Center for Nanotechnology of Saint Petersburg State University within the framework of project no.AAAAA19-119091190094supported by the Russian Science Foundation(project no.24-62-00022)Priority 2030 Federal Academic Leadership Program.
文摘Perovskite nanostructured films are essential to create advanced optoelectronic and photovoltaic devices because of the additional degrees of freedom of manipulation by light reflection and structural colouration,as well as by light trapping and localisation,resulting in control of intensity or polarisation of luminescence.In this paper,we report structural colouration and photoluminescence anisotropy in perovskite films deposited on a substrate with laser-induced periodic surface structures(LIPSSs)on a thin TiO_(2)layer.The LIPSS TiO_(2)layer improves charge extraction from the perovskite films,confirmed by a time-resolved photoluminescence analysis.The developed method of substrate nanostructuring does not damage the perovskite films,in contrast to direct laser ablation,imprinting by a mould,mechanical scratching with a cantilever,or plasma-chemical etching.Moreover,the LIPSS formation is appropriate for upscaling owing to the high speed of LIPSS writing(2.25 cm^(2)min^(-1))and uniform surface nanostructuring.
