A semiconductor optical amplifier gate based on tensile strained quasi bulk InGaAs is developed.At injection current of 80mA,a 3dB optical bandwidth of more than 85nm is achieved due to dominant band filling effect...A semiconductor optical amplifier gate based on tensile strained quasi bulk InGaAs is developed.At injection current of 80mA,a 3dB optical bandwidth of more than 85nm is achieved due to dominant band filling effect.Moreover,the most important is that very low polarization dependence of gain (<0 7dB),fiber to fiber lossless operation current (70～90mA) and a high extinction ratio (>50dB) are simultaneously obtained over this wide 3dB optical bandwidth (1520～1609nm) which nearly covers the spectral region of the whole C band (1525～1565nm) and the whole L band (1570～1610nm).The gating time is also improved by decreasing carrier lifetime.The wide band polarization insensitive SOA gate is promising for use in future dense wavelength division multiplexing (DWDM) communication systems.展开更多
Absorption coefficient of biological tissue is an important parameter in biomedicine, but its determination remains a challenge. In this paper, we propose a method using focusing photoacoustic imaging technique and in...Absorption coefficient of biological tissue is an important parameter in biomedicine, but its determination remains a challenge. In this paper, we propose a method using focusing photoacoustic imaging technique and internal light irradiation of cylindrical diffusing fiber(CDF) to quantify the target optical absorption coefficient. Absorption coefficients for ink absorbers are firstly determined through photoacoustic and spectrophotometric measurements at the same excitation, which demonstrates the feasibility of this method. Also, the optical absorption coefficients of ink absorbers with several concentrations are measured. Finally, the two-dimensional scanning photoacoustic image is obtained. Optical absorption coefficient measurement and simultaneous photoacoustic imaging of absorber non-invasively are the typical characteristics of the method. This method can play a significant role for non-invasive determination of blood oxygen saturation, the absorption-based imaging and therapy.展开更多
文摘A semiconductor optical amplifier gate based on tensile strained quasi bulk InGaAs is developed.At injection current of 80mA,a 3dB optical bandwidth of more than 85nm is achieved due to dominant band filling effect.Moreover,the most important is that very low polarization dependence of gain (<0 7dB),fiber to fiber lossless operation current (70～90mA) and a high extinction ratio (>50dB) are simultaneously obtained over this wide 3dB optical bandwidth (1520～1609nm) which nearly covers the spectral region of the whole C band (1525～1565nm) and the whole L band (1570～1610nm).The gating time is also improved by decreasing carrier lifetime.The wide band polarization insensitive SOA gate is promising for use in future dense wavelength division multiplexing (DWDM) communication systems.
基金supported by the National Natural Science Foundation of China(Nos.61675043 and 81571726)the Natural Science Foundation of Fujian Province(Nos.2015J01006 and 2017J01742)the Doctoral Scientific Research Foundation of Jimei University(No.ZQ2016005)
文摘Absorption coefficient of biological tissue is an important parameter in biomedicine, but its determination remains a challenge. In this paper, we propose a method using focusing photoacoustic imaging technique and internal light irradiation of cylindrical diffusing fiber(CDF) to quantify the target optical absorption coefficient. Absorption coefficients for ink absorbers are firstly determined through photoacoustic and spectrophotometric measurements at the same excitation, which demonstrates the feasibility of this method. Also, the optical absorption coefficients of ink absorbers with several concentrations are measured. Finally, the two-dimensional scanning photoacoustic image is obtained. Optical absorption coefficient measurement and simultaneous photoacoustic imaging of absorber non-invasively are the typical characteristics of the method. This method can play a significant role for non-invasive determination of blood oxygen saturation, the absorption-based imaging and therapy.
