We propose a stable and high optical signal-to-noise ratio(OSNR)compound linear-cavity single-longitudinal-mode(SLM)erbium-doped silica fiber laser.It consists of three uniform fiber Bragg gratings(FBGs)and two fiber ...We propose a stable and high optical signal-to-noise ratio(OSNR)compound linear-cavity single-longitudinal-mode(SLM)erbium-doped silica fiber laser.It consists of three uniform fiber Bragg gratings(FBGs)and two fiber couplers to form a simple asymmetric four-cavity structure to select the longitudinal mode.The stable SLM operation at the wavelength of 1544.053 nm with a 3 dB bandwidth of 0.014 nm and an OSNR of~60 dB was verified experimentally.Under laboratory conditions,a power fluctuation performance of less than 0.05 dB for 5 h and wavelength variation of less than 0.01 nm for about 150 min is demonstrated.Finally,the characteristic of laser output power as a function of pump power is investigated.The proposed system provides a simple and cost-effective approach to realize a stable SLM fiber laser.展开更多
The triangular-lattice highly birefringent photonic crystal fibers(PCFs) with gradually increasing diameter of the air holes along radial axis are put forward. The modal birefringence, dispersion and confinement loss ...The triangular-lattice highly birefringent photonic crystal fibers(PCFs) with gradually increasing diameter of the air holes along radial axis are put forward. The modal birefringence, dispersion and confinement loss of the fundamental mode are simulated by full vector Galerkin finite element method(FEM) with a perfectly matched layer(PML). The results show that this PCF can keep low confinement loss when the rings of air holes are few. When the wavelength is 1.55 μm , the birefringence, the confinement loss of quick-axis and slow-axis are 1.365×10-3, 0.017 dB/m and 0.051 dB/m, respectively. A new way is proposed to fabricate polarization-mainting fibers with high performance.展开更多
A simple approach for stable single polarization,single frequency,and linear cavity erbium doped fiber laser is proposed and demonstrated.A Fabry-Pérot filter,polarizer and saturable absorber are used together to...A simple approach for stable single polarization,single frequency,and linear cavity erbium doped fiber laser is proposed and demonstrated.A Fabry-Pérot filter,polarizer and saturable absorber are used together to ensure stable single frequency,single polarization operation.The optical signal-to-noise ratio of the laser is approximately 57 dB,and the Lorentz linewidth is 13.9 kHz.The polarization state of the laser with good stability is confirmed and the degree of polarization is>99%.展开更多
To the editor： Arrhythmogenic right ventricular cardiomyopathy （ARVC） is characterized by structural and fianctional abnormalities of the right ventricle due to replacement of the myocardium by fatty and fibrous ti...To the editor： Arrhythmogenic right ventricular cardiomyopathy （ARVC） is characterized by structural and fianctional abnormalities of the right ventricle due to replacement of the myocardium by fatty and fibrous tissue, often with involvement of the left ventricle （LV）. ARVC has been recognized as a cause of sudden death, especially in the young. We present a case of sudden death due to ARVC based on autopsy findings.展开更多
基金Supported by the National Natural Science Foundation of China(61077069,61107094)the Fundamental Research Funds for the Central Universities(2011YJS202,2011JBM001)。
文摘We propose a stable and high optical signal-to-noise ratio(OSNR)compound linear-cavity single-longitudinal-mode(SLM)erbium-doped silica fiber laser.It consists of three uniform fiber Bragg gratings(FBGs)and two fiber couplers to form a simple asymmetric four-cavity structure to select the longitudinal mode.The stable SLM operation at the wavelength of 1544.053 nm with a 3 dB bandwidth of 0.014 nm and an OSNR of~60 dB was verified experimentally.Under laboratory conditions,a power fluctuation performance of less than 0.05 dB for 5 h and wavelength variation of less than 0.01 nm for about 150 min is demonstrated.Finally,the characteristic of laser output power as a function of pump power is investigated.The proposed system provides a simple and cost-effective approach to realize a stable SLM fiber laser.
基金National Natural Science Foundation of China(No.60577034)
文摘The triangular-lattice highly birefringent photonic crystal fibers(PCFs) with gradually increasing diameter of the air holes along radial axis are put forward. The modal birefringence, dispersion and confinement loss of the fundamental mode are simulated by full vector Galerkin finite element method(FEM) with a perfectly matched layer(PML). The results show that this PCF can keep low confinement loss when the rings of air holes are few. When the wavelength is 1.55 μm , the birefringence, the confinement loss of quick-axis and slow-axis are 1.365×10-3, 0.017 dB/m and 0.051 dB/m, respectively. A new way is proposed to fabricate polarization-mainting fibers with high performance.
基金Supported by the National Natural Science Foundation of China (Nos 61077069 and 61275091)the Major State Basic Research Development Program of China (No 2010CB328206)the Colleges and Universities Science and Technology Research Project in Hebei Province (Z2011201).
文摘A simple approach for stable single polarization,single frequency,and linear cavity erbium doped fiber laser is proposed and demonstrated.A Fabry-Pérot filter,polarizer and saturable absorber are used together to ensure stable single frequency,single polarization operation.The optical signal-to-noise ratio of the laser is approximately 57 dB,and the Lorentz linewidth is 13.9 kHz.The polarization state of the laser with good stability is confirmed and the degree of polarization is>99%.
文摘To the editor： Arrhythmogenic right ventricular cardiomyopathy （ARVC） is characterized by structural and fianctional abnormalities of the right ventricle due to replacement of the myocardium by fatty and fibrous tissue, often with involvement of the left ventricle （LV）. ARVC has been recognized as a cause of sudden death, especially in the young. We present a case of sudden death due to ARVC based on autopsy findings.
