A fitting process is used to measure the cavity loss and the quasi Fermi level separation for Fabry Pérot semiconductor lasers.From the amplified spontaneous emission (ASE) spectrum,the gain spectrum and sing...A fitting process is used to measure the cavity loss and the quasi Fermi level separation for Fabry Pérot semiconductor lasers.From the amplified spontaneous emission (ASE) spectrum,the gain spectrum and single pass ASE obtained by the Cassidy method are applied in the fitting process.For a 1550nm quantum well InGaAsP ridge waveguide laser,the cavity loss of about ～24cm -1 is obtained.展开更多
A novel gain measurement technique based on the integration of the measured amplified spontaneous emission spectrum multiplying a phase function over one longitudinal mode interval is proposed for Fabry-Perot semicond...A novel gain measurement technique based on the integration of the measured amplified spontaneous emission spectrum multiplying a phase function over one longitudinal mode interval is proposed for Fabry-Perot semiconductor lasers.展开更多
Based on the moiré effect and the Fresnel diffraction theory, a novel technique for diagnosing the beam properties is presented and analyzed, which is especially suitable for X-ray lasers. The method makes it pos...Based on the moiré effect and the Fresnel diffraction theory, a novel technique for diagnosing the beam properties is presented and analyzed, which is especially suitable for X-ray lasers. The method makes it possible, in a one-shot experimental measurement, to determine the beam quality factor M2, the effective radius of curvature, the beam width, the far-field divergence, and the waist location and radius as well as the spatial coherence and its evolution. Numerical simulation proves the validity of the method. Note that the novel moiré technique opens an efficient road, for the first time, to fully diagnose the spatial properties of X-ray lasers.展开更多
文摘A fitting process is used to measure the cavity loss and the quasi Fermi level separation for Fabry Pérot semiconductor lasers.From the amplified spontaneous emission (ASE) spectrum,the gain spectrum and single pass ASE obtained by the Cassidy method are applied in the fitting process.For a 1550nm quantum well InGaAsP ridge waveguide laser,the cavity loss of about ～24cm -1 is obtained.
基金This work was supported by the National Nature Science Foundation of China under grants No. 60225011major state basic research program under grant No. G2000036606.
文摘A novel gain measurement technique based on the integration of the measured amplified spontaneous emission spectrum multiplying a phase function over one longitudinal mode interval is proposed for Fabry-Perot semiconductor lasers.
基金supported by the National High Technology Research and Development Program of China.
文摘Based on the moiré effect and the Fresnel diffraction theory, a novel technique for diagnosing the beam properties is presented and analyzed, which is especially suitable for X-ray lasers. The method makes it possible, in a one-shot experimental measurement, to determine the beam quality factor M2, the effective radius of curvature, the beam width, the far-field divergence, and the waist location and radius as well as the spatial coherence and its evolution. Numerical simulation proves the validity of the method. Note that the novel moiré technique opens an efficient road, for the first time, to fully diagnose the spatial properties of X-ray lasers.
