Effective multiple optoelectronic feedback circuits for simultaneously suppressing low-frequency and relaxation oscillation intensity noise in a single-frequency phosphate fiber laser are demonstrated. The forward tra...Effective multiple optoelectronic feedback circuits for simultaneously suppressing low-frequency and relaxation oscillation intensity noise in a single-frequency phosphate fiber laser are demonstrated. The forward transfer function, which relates the laser output intensity to the pump modulations, is measured and analyzed. A custom two-path feedback system operating at different frequency bands is designed to adjust the pump current directly. The relative intensity noise is decreased by 20dB from 0.2 to 5kHz and over lOdB from 5 to lOkHz. The relaxation oscillation peak is suppressed by 22dB. In addition, a long term （24h） laser instability of less than 0.05% is achieved.展开更多
A modified continuous-variable quantum key distribution （CVQKD） protocol is proposed by originating the entangled source from a malicious third party Eve in the middle instead of generating it from the trustworthy A...A modified continuous-variable quantum key distribution （CVQKD） protocol is proposed by originating the entangled source from a malicious third party Eve in the middle instead of generating it from the trustworthy Alice or Bob. This method is able to enhance the efficiency of the CVQKD scheme attacked by local oscillator （LO） intensity attack in terms of the generated secret key rate in quantum communication. The other indication of the improvement is that the maximum transmission distance and the maximum loss tolerance can be increased significantly, especially for CVQKD schemes based on homodyne detection.展开更多
We present a multi-level growth model that yields some of the key features of perovskite oxide film growth as observed in the reflection high energy electron diffraction （RHEED） and ellipsometry studies. The model d...We present a multi-level growth model that yields some of the key features of perovskite oxide film growth as observed in the reflection high energy electron diffraction （RHEED） and ellipsometry studies. The model describes the effect of deposition, temperature, intra-layer transport, interlayer transport and Ostwald ripening on the morphology of a growth surface in terms of the distribution of terraces and step edges during and after deposition. The numerical results of the model coincide well with the experimental observation.展开更多
基金Supported by the National High-Technology Research and Development Program of China under Grant Nos 2013AA031502 and 2014AA041902the National Natural Science Foundation of China under Grant Nos 11174085,51132004,and 51302086+3 种基金the Guangdong Natural Science Foundation under Grant Nos S2011030001349 and S20120011380the China National Funds for Distinguished Young Scientists under Grant No 61325024the Science and Technology Project of Guangdong Province under Grant No 2013B090500028the’Cross and Cooperative’Science and Technology Innovation Team Project of Chinese Academy of Sciences under Grant No 2012-119
文摘Effective multiple optoelectronic feedback circuits for simultaneously suppressing low-frequency and relaxation oscillation intensity noise in a single-frequency phosphate fiber laser are demonstrated. The forward transfer function, which relates the laser output intensity to the pump modulations, is measured and analyzed. A custom two-path feedback system operating at different frequency bands is designed to adjust the pump current directly. The relative intensity noise is decreased by 20dB from 0.2 to 5kHz and over lOdB from 5 to lOkHz. The relaxation oscillation peak is suppressed by 22dB. In addition, a long term （24h） laser instability of less than 0.05% is achieved.
基金supported by the National Natural Science Foundation of China(Grant Nos.61379153,61401519,and 61572529)the Natural Science Foundation of Hunan Province,China(Grant No.2017JJ3415)+1 种基金the Science and Technology Project of Guangxi Zhuang Autonomous Region,China(Grant Nos.AC16380094and 1598008-29)the Natural Science Fund of Guangxi Zhuang Autonomous Region,China(Grant No.2015GXNSFAA139298)
文摘A modified continuous-variable quantum key distribution （CVQKD） protocol is proposed by originating the entangled source from a malicious third party Eve in the middle instead of generating it from the trustworthy Alice or Bob. This method is able to enhance the efficiency of the CVQKD scheme attacked by local oscillator （LO） intensity attack in terms of the generated secret key rate in quantum communication. The other indication of the improvement is that the maximum transmission distance and the maximum loss tolerance can be increased significantly, especially for CVQKD schemes based on homodyne detection.
文摘We present a multi-level growth model that yields some of the key features of perovskite oxide film growth as observed in the reflection high energy electron diffraction （RHEED） and ellipsometry studies. The model describes the effect of deposition, temperature, intra-layer transport, interlayer transport and Ostwald ripening on the morphology of a growth surface in terms of the distribution of terraces and step edges during and after deposition. The numerical results of the model coincide well with the experimental observation.
