Author Affiliations
Abstract
State Key Laboratory of Tunable Laser Technology, Ministry of Industry and Information Technology, Key Laboratory of Micro-Nano Optoelectronic Information System, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, China
Magnetic dipole (MD) transitions are important for a range of technologies from quantum light sources and displays to lasers and bio-probes. However, the typical MD transitions are much weaker than their electric counterparts and are usually neglected in practical applications. Herein, we experimentally demonstrate that the MD transitions can be significantly enhanced by the well-developed magnetic metamaterials in the visible optical range. The magnetic metamaterials consist of silver nanostrips and a thick silver film, which are separated with an Eu3+:polymethyl methacrylate (PMMA) film. By controlling the thickness of the Eu3+:PMMA film, the magnetic resonance has been tuned to match the emission wavelength of MDs. Consequently, the intensity of MD emission has been significantly increased by around 30 times at the magnetic resonance wavelength, whereas the intensity of electric dipole emission is well-preserved. The corresponding numerical calculations reveal that the enhancement is directly generated by the magnetic resonance, which strongly increases the magnetic local density of states around the MD emitter and can efficiently radiate the MD emission into the far field. This is the first demonstration, to the best of our knowledge, that MD transitions can be improved by an additional degree of magnetic freedom, and we believe this research shall pave a new route towards bright magnetic emitters and their potential applications.
160.3918 Metamaterials 160.6990 Transition-metal-doped materials 350.5400 Plasmas 310.6628 Subwavelength structures,nanostructures 300.6550 Spectroscopy, visible Chinese Optics Letters
2018, 16(5): 050008
Author Affiliations
Abstract
1 Gemstone Testing Center, East China University of Science & Technology, Shanghai 200237, China
2 Jewelry College, Shanghai Jian Qiao University, Shanghai 201306, China
3 Research Center of Analysis and Test, East China University of Science & Technology, Shanghai 200237, China
A light purplish red sapphire is heat treated in an airtight crucible. The sample changes little in color after receiving heat treatment at 1100°C, but turns to light blue and blue after being treated at 1200°C and 1300°C, respectively. Before heating, the UV-VIS absorption spectra of the sample are dominated by the 551 nm broad absorption band contributed by the d-electron transition A24→T24 of Cr3+. After heating, the UV-VIS absorption spectra are dominated by the 563 nm broad absorption band contributed by the intervalence charge transfer of Fe2+ Ti4+. The x ray photoelectron spectroscopy test reveals that the Fe2+ and Ti4+ ion contents increase with increasing temperature. The sapphire changing from light purplish red to blue in the heating process is owing to the fact that the Fe2+ and Ti4+ contents grow and the intervalence charge transfer of Fe2+ Ti4+ selectively absorbs UV-VIS light.
300.6550 Spectroscopy, visible 300.1030 Absorption 300.6170 Spectra Chinese Optics Letters
2016, 14(5): 053001
Author Affiliations
Abstract
According to the LED spectra measured in the rated current, Gauss distribution function and asymmetric Gaussian distribution function methods are used to simulate the individual LED spectrum. Based on this mathematical model, 32 LEDs are used to synthesize arbitrary spectral distribution of the light source. Processing the spectral data with multiple linear regressions, CIE illuminant A and CIE illuminant D65 are simulated. The results show that for each LED, different Gauss models should be used. The simulation results are quite satisfying. However, there is a difference between the simulation results and the experimental results. The spectral evaluation indices of fitted both CIE illuminant A and CIE illuminant D65 do not exceed 2.5%. But in experiment, because of the changes of the peak wavelength and the FWHM caused by the current, the spectral evaluation indices of fitted CIE illuminant A and CIE illuminant D65 are around 5%.
230.3670 Light-emitting diodes 240.6380 Spectroscopy, modulation 300.6550 Spectroscopy, visible Chinese Optics Letters
2014, 12(3): 032301
Author Affiliations
Abstract
Seven color separation criteria are evaluated and compared for multi-ink printer characterization, which is a union of five 3-ink and six 4-ink cellular Yule-Nielsen spectral Neugebauer (CYNSN) submodels. In the experimental stage, testing reflectances from printing samples and Munsell color samples are employed. The results show that the prediction and actual accuracy of all the seven selection criteria are approximately the same for printing samples. As for the Munsell samples, the combE00 &MI outperforms other selection criteria because it combines one color difference with two metamerism indices, which are important for the heterogeneous samples during prediction.
330.1690 Color 300.6550 Spectroscopy, visible 330.1710 Color, measurement 330.1715 Color, rendering and metamerism Chinese Optics Letters
2012, 10(1): 013301
Author Affiliations
Abstract
1 State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027, China
2 Department of Colour Science, University of Leeds, Leeds LS2 9JT, UK
Conventional printer characterisation models are generally based on the assumption that the densities of primary colours are additive. However, additivity failure frequently occurs in practice. We propose a novel grey component replacement (GCR) method based on the spectral density sub-additivity equations in this letter for spectral characterisation of a 4-ink colour printer. The method effectively correct the error caused by additivity failure. Real high-quality hardcopy samples are produced as evidence of the feasibility of the proposed method and to evaluate the model performance. Finally, the GCR model for characterising colour printer with high spectral and colorimetric prediction accuracy is established.
光谱特征化 灰份替代 光谱密度 叠加特性缺失 次叠加特性方程。 330.1690 Color 330.1715 Color, rendering and metamerism 330.1730 Colorimetry 300.6550 Spectroscopy, visible Chinese Optics Letters
2011, 9(7): 073301
Author Affiliations
Abstract
Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
Using 300-fs 1039-nm Yb-doped fiber laser, we experimentally demonstrate blue light generation in a high-\Delta and high nonlinear photonic crystal fiber (PCF). The zero dispersion wavelength of PCF is 793 nm, detuning 245.8 nm from the pump wavelength. PCF allows a frequency conversion exceeding the octave of pump wavelength. The visible component of the measured output spectrum occurs in the fundamental mode and spans from 391.3 to 492.3 nm. The peak wavelength of 441.8 nm has a frequency detuning of 390 THz from the pump wavelength of 1039 nm.
光子晶体光纤 蓝色可见光 掺镱飞秒光纤激光器 190.7220 Upconversion 300.6550 Spectroscopy, visible 320.6629 Supercontinuum generation Chinese Optics Letters
2011, 9(7): 071901
Author Affiliations
Abstract
1 State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027, China
2 Department of Colour Science, University of Leeds, Leeds, LS2 9JT, UK
A spectral-based 8-ink characterization model is developed to accurately predict the recipe for a multi-ink printer. The 8-ink color separation method is a union of five 3-ink and six 4-ink combinations based on the cellular Yule-Nielsen spectral Neugebauer model with a recipe selection strategy. The performance levels of the forward and backward models are evaluated for individual ink combinations using printed testing samples. Furthermore, the spectral-based method performs better compared with the XYZ-based approach. On the basis of the backward model performance, a novel fast recipe selection strategy is proposed and estimated.
打印系统特征化 分色 光谱式Neugebauer模型 多墨打印机 配方选择策略。 330.1690 Color 300.6550 Spectroscopy, visible 330.1710 Color, measurement 330.1715 Color, rendering and metamerism Chinese Optics Letters
2011, 9(6): 063301
Author Affiliations
Abstract
1 State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027, China
2 Department of Colour Science, University of Leeds, Leeds LS2 9JT, UK
The cellular Yule-Nielson spectral Neugebauer (CYNSN) model to characterize a typical CMYK (i.e., cyan, magenta, yellow, and black) 4-ink color printer is presented. By reconstructing spectral reflectance, models with high accuracy of spectral and colorimetric predictions are built. A novel cell-searching algorithm is proposed and used together with the iteration method to invert the cellular Neugebauer model efficiently. Large numbers of high quality hardcopy samples are produced to evaluate model performance and prove the feasibility of the algorithm. The spectral-based model performs better compared with the usual model based on CIE1931 XYZ tristimulus values.
光谱颜色复现 分格状Neugebauer模型 打印系统特征化 胞元搜索算法 330.1690 Color 330.1715 Color, rendering and metamerism 330.1730 Colorimetry 300.6550 Spectroscopy, visible Chinese Optics Letters
2010, 8(11): 1106
Author Affiliations
Abstract
1 Key Laboratory of Material Science and Technology for High Power Lasers, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China
The growth of a Mn-doped LiAlO2 single crystal by the Czochralski (CZ) method and the characterization of its spectroscopy and thermoluminescence (TL) are presented. The X-ray rocking curve and chemical etching analysis show that the as-grown crystal has good crystallinity. The full-width at half-maximum (FWHM) of the LiAlO2 (200) \omega rocking curve is 23.2 arcsec and the etching pits density of the (100) plane is (1.6–4.0)×104 cm-2. The transmission spectrum indicates that the crystal is highly transparent in the 200–1500-nm wavelength range. The emission spectrum of the crystal consists of a peak around 579 nm when excited with 428-nm light. The TL spectra show that the LiAlO2:Mn crystal has glow peaks at 150 and 172 ℃. The change of TL characteristics of the crystal before and after thermal annealing in the air is discussed, and the effect of annealing and irradiation on the evolution of defect types is analyzed.
LiAlO2:Mn晶体 提拉法 结晶质量 光谱 热释光 160.2220 Defect-center materials 160.6990 Transition-metal-doped materials 300.6280 Spectroscopy, fluorescence and luminescence 300.6550 Spectroscopy, visible Chinese Optics Letters
2010, 8(4): 414
Author Affiliations
Abstract
1
2 Department of Chemistry, Material Science and Engineering College, Southwest University of Science and Technology, Mianyang 621010, China
The action mode between Dy(III)(NR)3 and herring sperm DNA is studied by ultraviolet-visible (UV-vis) and fluorescence spectra as well as electrochemistry. Double-reciprocal method studies show that the binding stoichiometry between Dy(III)(NR)3 and DNA is 1:1, the binding constants at different temperatures are 1。15×105 L/mol at 25 ℃ and 2.09×105 L/mol at 35 ℃, and the corresponding thermodynamic parameters are \DeltarH \mathrm m = 2.48×104 J/mol, \DeltarG \mathrm m =-2.34×104 J/mol, \DeltarSm=161.7 J/(mol·K); \DeltarS \mathrm m is the driving force in this reaction. Combined with Scatchard method and melting method, the results suggest that the interaction mode between Dy(III)(NR)3 and herring sperm DNA is intercalation fashion and groove fashion.
Dy(Ⅲ)(NR)3配合物 鲱鱼精DNA 吖啶橙 作用模式 300.6390 Spectroscopy, molecular 300.6280 Spectroscopy, fluorescence and luminescence 300.6550 Spectroscopy, visible Chinese Optics Letters
2010, 8(2): 236
