All-optical wavelength conversion has been demonstrated with an electroabsorption modulator based on cross-absorption modulation. For the first time, simultaneous broadcasting up to 6 different wavelengths at 10Gb/s i...All-optical wavelength conversion has been demonstrated with an electroabsorption modulator based on cross-absorption modulation. For the first time, simultaneous broadcasting up to 6 different wavelengths at 10Gb/s is obtained with less than 0.5-dB polarization dependence.展开更多
A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optica...A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optical core layers plays a key role in high-speed and high-extinction operation.展开更多
Electroabsorption (EA) measurements on thin films of poly[ o (trimethylsilyl) phenylacetylene] and poly[ o (trimethylsilylmethyl) phenylacetylene] have been performed. The spectral change induced by an exernal electri...Electroabsorption (EA) measurements on thin films of poly[ o (trimethylsilyl) phenylacetylene] and poly[ o (trimethylsilylmethyl) phenylacetylene] have been performed. The spectral change induced by an exernal electric field (EA spectra) has been observed, which shows the similar shape of the second derivative of the optical absorption spectra. The change in the absorption Δ α is obtained from the EA spectrum, and Δ n is calculated through Kramers_Krong transformation. The optical properties of substituted polyphenylacetylenes (PPAs) were discussed.展开更多
We have proposed a new model for the calculation of excitonic electroabsorption based on modified previously reported models for bulk structure. The excitonic absorption spectra in high purity GaAs have been theoretic...We have proposed a new model for the calculation of excitonic electroabsorption based on modified previously reported models for bulk structure. The excitonic absorption spectra in high purity GaAs have been theoretically studied in the presence of electric field at room temperature (RT). The Stark shift, linewidth broadening of exciton and extinction ratio have been calculated as a function of electric field. For the validity of our model we have compared with experimental result.展开更多
The determination of nonlinearities near the band edge of organic and polymeric electro-optic(EO)materials is important from the viewpoint of molecular nonlinear optics(NLO)and photonic device applications.Based on tr...The determination of nonlinearities near the band edge of organic and polymeric electro-optic(EO)materials is important from the viewpoint of molecular nonlinear optics(NLO)and photonic device applications.Based on transmission-mode Stark effect electromodulation(EM)spectroscopy,we study the electric-field-induced changes in optical absorption and refraction of newly developed EO polymers from the visible to near-infrared(NIR)wavelengths and report record-high near-band-edge complex EO effects from poled thin films.Values ofΔn andΔk up to 10^(-3) and 10^(-2) are found at an applied electric field of 2.0×10^(5)-3.0×10^(5)V/cm.The study of linear optical properties of poled films by spectroscopic ellipsometry shows large polinginduced birefringence and a nearly two-fold increase in the extinction coefficients at the extraordinary polarization.Through the Kramers-Kronig analysis,we obtained the real and imaginary second-order nonlinear coefficients up to~3,500 and~5,600 pm/V,respectively,which are believed to be the highest NLO coefficients of poled polymers through the resonance enhancement.Our approach goes beyond the previous works,applicable only to several discrete wavelengths,to a full-spectral analysis with independent verification of slab waveguide measurements.By considering both the electroabsorption and electrorefraction effects,our study overcomes the limitation of the classic qualitative two-level model and provides a quantitative understanding of near-resonance optical nonlinearities of organic EO materials.It can inspire the exploration of high-speed,absorptive,or phase-shifting light-modulators using EO polymers for on-chip applications.展开更多
文摘All-optical wavelength conversion has been demonstrated with an electroabsorption modulator based on cross-absorption modulation. For the first time, simultaneous broadcasting up to 6 different wavelengths at 10Gb/s is obtained with less than 0.5-dB polarization dependence.
文摘A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optical core layers plays a key role in high-speed and high-extinction operation.
文摘Electroabsorption (EA) measurements on thin films of poly[ o (trimethylsilyl) phenylacetylene] and poly[ o (trimethylsilylmethyl) phenylacetylene] have been performed. The spectral change induced by an exernal electric field (EA spectra) has been observed, which shows the similar shape of the second derivative of the optical absorption spectra. The change in the absorption Δ α is obtained from the EA spectrum, and Δ n is calculated through Kramers_Krong transformation. The optical properties of substituted polyphenylacetylenes (PPAs) were discussed.
文摘We have proposed a new model for the calculation of excitonic electroabsorption based on modified previously reported models for bulk structure. The excitonic absorption spectra in high purity GaAs have been theoretically studied in the presence of electric field at room temperature (RT). The Stark shift, linewidth broadening of exciton and extinction ratio have been calculated as a function of electric field. For the validity of our model we have compared with experimental result.
基金supported by the Fundamental Research Project Funding from Shenzhen Science & Technology Innovation Committee (JCYJ20180507181718203)the National Natural Science Foundation of China (21975213)+2 种基金the Research Grants Council (RGC) of Hong Kong (11306320, 11303618, 11210218)the City University of Hong Kong (9610389, 9680263, 9610454)the Innovation and Technology Commission of Hong Kong (ITS/461/18)。
文摘The determination of nonlinearities near the band edge of organic and polymeric electro-optic(EO)materials is important from the viewpoint of molecular nonlinear optics(NLO)and photonic device applications.Based on transmission-mode Stark effect electromodulation(EM)spectroscopy,we study the electric-field-induced changes in optical absorption and refraction of newly developed EO polymers from the visible to near-infrared(NIR)wavelengths and report record-high near-band-edge complex EO effects from poled thin films.Values ofΔn andΔk up to 10^(-3) and 10^(-2) are found at an applied electric field of 2.0×10^(5)-3.0×10^(5)V/cm.The study of linear optical properties of poled films by spectroscopic ellipsometry shows large polinginduced birefringence and a nearly two-fold increase in the extinction coefficients at the extraordinary polarization.Through the Kramers-Kronig analysis,we obtained the real and imaginary second-order nonlinear coefficients up to~3,500 and~5,600 pm/V,respectively,which are believed to be the highest NLO coefficients of poled polymers through the resonance enhancement.Our approach goes beyond the previous works,applicable only to several discrete wavelengths,to a full-spectral analysis with independent verification of slab waveguide measurements.By considering both the electroabsorption and electrorefraction effects,our study overcomes the limitation of the classic qualitative two-level model and provides a quantitative understanding of near-resonance optical nonlinearities of organic EO materials.It can inspire the exploration of high-speed,absorptive,or phase-shifting light-modulators using EO polymers for on-chip applications.
