We have developed a novel optical fiber ring laser using a semiconductor optical amplifier (SOA) as the gain medium, and taking advantage of polarization anisotropy of its gain. The frequency difference of the bi-dire...We have developed a novel optical fiber ring laser using a semiconductor optical amplifier (SOA) as the gain medium, and taking advantage of polarization anisotropy of its gain. The frequency difference of the bi-directional laser is controlled by birefringence which is introduced in the ring laser cavity. The beat frequency generated by combining two counter-propagating oscillations is proportional to the birefringence, the fiber ring laser of the present study is, therefore, applicable to the fiber sensor. The sensing signal is obtained in a frequency domain with the material which causes the retardation change by a physical phenomenon to be measured. For the application to stress sensing, the present laser was investigated with a photoelastic material.展开更多
A simple and cost-effective multi-wavelength fiber ring laser based on a chirped Moire fiber grating (CMFG) and a semiconductor optical amplifier (SOA) is proposed. Stable triple-wavelength lasing oscillations at ...A simple and cost-effective multi-wavelength fiber ring laser based on a chirped Moire fiber grating (CMFG) and a semiconductor optical amplifier (SOA) is proposed. Stable triple-wavelength lasing oscillations at room temperature are experimentally demonstrated. The measured optical signal-to-noise ratio (SNR) reaches the highest value of 50 dB and the power fluctuation of each wavelength is less than 0.2 dB within a 1-h period. To serve as a wavelength selective element, the CMFG possesses excellent comb-like filtering characteristics including stable wavelength interval and ultra-narrow passband, and its fabrication method is easy and flexible. The lasing oscillation shows a narrower bandwidth than SOA-based multi-wavelength fiber lasers utilizing some other kinds of wavelength selective components. Methods to optimize the laser performance are also discussed.展开更多
Multi-wavelength fiber ring laser based on the semiconductor optical amplifier(SOA)with sampled fiber Bragg grating(SFBG)in a Sagnac loop interferometer as the wavelength-selective filter is proposed.Four lasing wavel...Multi-wavelength fiber ring laser based on the semiconductor optical amplifier(SOA)with sampled fiber Bragg grating(SFBG)in a Sagnac loop interferometer as the wavelength-selective filter is proposed.Four lasing wavelengths with 1.8 nm spacing have been generated stably at room temperature.The proposed laser has the advan-tages such as removal of the high-cost circulator,flexibility in channel-spacing tuning,and simple all-optical fiber configuration,which has potential applications in high-capacity wavelength-division-multiplexed(WDM)systems and mechanical sensors.展开更多
We demonstrate a 1550-nm narrow-linewidth fiber ring laser with stable single polarization by using single-mode Er-doped fiber as active fiber and saturable absorber. A polarization-maintaining circulator is used to a...We demonstrate a 1550-nm narrow-linewidth fiber ring laser with stable single polarization by using single-mode Er-doped fiber as active fiber and saturable absorber. A polarization-maintaining circulator is used to acquire single-polarization laser light with the degree of polarization of 99.8%--99.9%. The linewidth measured using a delayed self-heterodyne method is less than 0.5 kHz. Frequency of the fiber laser can be modulated by driving the waveguide phase modulator with proper voltage. A Mach-Zehnder interferometer with the optical path difference between two arms of about 36 km is used to study the long-distance coherent detection of the fiber laser for frequency-modulated continuous-wave application.展开更多
文摘We have developed a novel optical fiber ring laser using a semiconductor optical amplifier (SOA) as the gain medium, and taking advantage of polarization anisotropy of its gain. The frequency difference of the bi-directional laser is controlled by birefringence which is introduced in the ring laser cavity. The beat frequency generated by combining two counter-propagating oscillations is proportional to the birefringence, the fiber ring laser of the present study is, therefore, applicable to the fiber sensor. The sensing signal is obtained in a frequency domain with the material which causes the retardation change by a physical phenomenon to be measured. For the application to stress sensing, the present laser was investigated with a photoelastic material.
基金supported by the National Natural Science Foundation of China (No.60771008)the National "863" Program of China (No.2007AA01Z258)+1 种基金the Support Plan for New Century Excellent Talents (No.NCET-05-0091)the Science Fund of Beijing Jiaotong University (No.2007XM003)
文摘A simple and cost-effective multi-wavelength fiber ring laser based on a chirped Moire fiber grating (CMFG) and a semiconductor optical amplifier (SOA) is proposed. Stable triple-wavelength lasing oscillations at room temperature are experimentally demonstrated. The measured optical signal-to-noise ratio (SNR) reaches the highest value of 50 dB and the power fluctuation of each wavelength is less than 0.2 dB within a 1-h period. To serve as a wavelength selective element, the CMFG possesses excellent comb-like filtering characteristics including stable wavelength interval and ultra-narrow passband, and its fabrication method is easy and flexible. The lasing oscillation shows a narrower bandwidth than SOA-based multi-wavelength fiber lasers utilizing some other kinds of wavelength selective components. Methods to optimize the laser performance are also discussed.
基金supported by the National“863” Project of China(2007AA01Z258)the National Natural Science Foundation of China(60771008)+2 种基金Program for New Century Excellent Talents in University(NCET-06-0076)Beijing Natural Science Foundation(4082024)the Beijing Jiaotong University Foundation(2006XM003)
文摘Multi-wavelength fiber ring laser based on the semiconductor optical amplifier(SOA)with sampled fiber Bragg grating(SFBG)in a Sagnac loop interferometer as the wavelength-selective filter is proposed.Four lasing wavelengths with 1.8 nm spacing have been generated stably at room temperature.The proposed laser has the advan-tages such as removal of the high-cost circulator,flexibility in channel-spacing tuning,and simple all-optical fiber configuration,which has potential applications in high-capacity wavelength-division-multiplexed(WDM)systems and mechanical sensors.
文摘We demonstrate a 1550-nm narrow-linewidth fiber ring laser with stable single polarization by using single-mode Er-doped fiber as active fiber and saturable absorber. A polarization-maintaining circulator is used to acquire single-polarization laser light with the degree of polarization of 99.8%--99.9%. The linewidth measured using a delayed self-heterodyne method is less than 0.5 kHz. Frequency of the fiber laser can be modulated by driving the waveguide phase modulator with proper voltage. A Mach-Zehnder interferometer with the optical path difference between two arms of about 36 km is used to study the long-distance coherent detection of the fiber laser for frequency-modulated continuous-wave application.