作者：
李犇陈景标Institute of Quantum Electronics
and State Key Laboratory of Advanced Optical Communication System & Network School of Electronics Engineering & Computer Science Peking University Beijing 100871
The collapse and revival of evolution with photon number of population inversion in the case of an atomic beam with velocity distribution interacting with a single-mode and Fock-state light field is investigated by fu...
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The collapse and revival of evolution with photon number of population inversion in the case of an atomic beam with velocity distribution interacting with a single-mode and Fock-state light field is investigated by full quantum theory. Compared to the previously reported coherent state case [Li B and Chen J B Chin. Phys. Lett. 26（2009）123203], which was induced by evolution with coupling strength of population inversion, in the case under consideration there exists Poisson distribution of photon numbers and atomic velocity distribution in the beam. Moreover, we prove that above, the collapse and revival have an analogy with conventional collapse and revival [Eberly J H et al. Phys. Rev. Lett. 44（1980）1323] in both the mathematical expression and physical significance.
作者：
李犇陈景标Institute of Quantum Electronics
and State Key Laboratory of Advanced Optical Communication System and Network School of Electronics Engineering and Computer Science Peking University Beijing 100871
We report on the phenomena of the periodic spontaneous collapse and revival in the dynamics of an atomic beam interacting with a single-mode and coherent-state light field. Conventional collapse and revival by Eberly ...
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We report on the phenomena of the periodic spontaneous collapse and revival in the dynamics of an atomic beam interacting with a single-mode and coherent-state light field. Conventional collapse and revival by Eberly et al. [Phys. Rev. Lett. 44（1980）1323 ] are presented in the case of the evolution with time of the population inversion. Here, we study the evolution with coupling strength of population inversion. We define the collapse and revival coupling strengths as characteristic parameters to describe the above collapse and revival. Furthermore, we present the analytic formulas for the population inversion, the collapse and revival coupling strengths.
作者：
谢俊陈玉萍陆闻杰陈险峰Department of Physics
State Key Laboratory on Fiber-Optic Local Area Network and Advanced Optical Communication SystemsShanghai Jiaotong University
Based on the second-order nonlinearity, we present a bidirectional tunable all-optical switch at C-band by introducing backward quasi-phase-matching technique in Mg-doped periodically poled lithium niobate （MgO：PPLN...
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Based on the second-order nonlinearity, we present a bidirectional tunable all-optical switch at C-band by introducing backward quasi-phase-matching technique in Mg-doped periodically poled lithium niobate （MgO：PPLN） waveguide with a nano-structure called multiple resonators. Two injecting forward lights and one backward propagating light interact with difference frequency generations. The transmission of forward signal and backward idler light can be modulated simultaneously with the variation of control light power based on the basic ＂phase shift＂ structure of a single resonator. In this scheme, all the results come from our simulation. The speed of this bidirectional optical switch can reach to femtosecond if a femtosecond laser is used as the control light.
We report on a compact passive mode-locked Er:fiber ring laser operated at the fundamental repetition rate of 517 MHz, which we believe is the highest fundamental repetition rate ever reported in a ring cavity fiber *...
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We report on a compact passive mode-locked Er:fiber ring laser operated at the fundamental repetition rate of 517 MHz, which we believe is the highest fundamental repetition rate ever reported in a ring cavity fiber *** key technique is the employment of two innovative high-power wavelength domain multiplexer collimators with all gain fiber cavity suited for the high power(up to 2 W) pumping. The laser is featured with a direct chirpfree output pulse, which is 97 fs without extracavity compression at an average output power of 90 mW.
作者：
周琢尔石剑虹陈险峰Department of Physics
The State Key Laboratory on Fiber-Optic Local Area Network and Advanced Optical Communication SystemsShanghai Jiao Tong University
We demonstrate a quasi-periodic structure exhibiting multiple photonic band gaps （PBGs） based on sub- micron-period poled lithium niobate （LN）. The structure consists of two building blocks, each containing a pair...
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We demonstrate a quasi-periodic structure exhibiting multiple photonic band gaps （PBGs） based on sub- micron-period poled lithium niobate （LN）. The structure consists of two building blocks, each containing a pair of antiparallel poled domains, arranged as a Fibonacci sequence. The gap wavelengths are analyzed with the Fibonacci sequence parameters such as the quasiperiodic indices and the average lattice parameter. The transmission properties are investigated by a traditional 4×4 matrix method. It has also been proved that the gap depth can be tuned by the lengths of poled domains.
作者：
孔艳陈险峰夏宇兴Department of Physics
The State Key Laboratory on Fiber Optic Local Area Communication Networks and Advanced Optical Communication System Shanghai Jiao Tong University Shanghai 200240
In order to minimize the effect of the unconsidered frequency components on the generated compression pulse, the phasing-blanking effect is taken into account of designing the one^dimensionai aperiodic domain reversal...
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In order to minimize the effect of the unconsidered frequency components on the generated compression pulse, the phasing-blanking effect is taken into account of designing the one^dimensionai aperiodic domain reversal structure. Hierarchic genetic algorithm for the design of a domain reversal grating to modulate the spectrum and phase of the generated SH pulse simultaneously are presented. Our simulation shows that the quality of an output pulse is fairly improved.
The experimental scheme of 633 nm and 1359 nm good-bad cavity dual-wavelength active optical frequency stan- dard is proposed, where He-Ne 633nm and Cs 1359nm stimulated emissions are working at good-cavity and bad-ca...
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The experimental scheme of 633 nm and 1359 nm good-bad cavity dual-wavelength active optical frequency stan- dard is proposed, where He-Ne 633nm and Cs 1359nm stimulated emissions are working at good-cavity and bad-cavity regimes, respectively. The cavity length is stabilized by locking the 633nm output frequency to a super-cavity with the Pound Drever-Hall （PDH） technique. The frequency stability of 1359 nm bad-cavity stim- ulated emission output is then expected to be further improved by at least 1 order of magnitude than the 633nm PDH system due to the suppressed cavity pulling effect of active optical clock, and the quantum limited linewidth of 1359nm output is estimated to be 72.5 mHz.
Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in ea...
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Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in each run of the experiment, by the combination of the Majorana transition according to the exponential modulation of the magnetic field pulse decline curve and radio frequency coupling among multiple magnetic *** to the realization of two Majorana transitions, the interference fringe for the magnetic field insensitive state also has a higher contrast. After spatially overlapping the full magnetic sub-state interference patterns dozens of times in consecutive experimental measurements, clear fringes are still observed, indicating the great stability of the relative phases of different components. This indicates the potential to achieve an interferometer with multiple spin clocks.
The sub-Doppler absorption laser spectroscopy at 728nm transition from the 5D5/2 state to the 6F state of cesium with linewidth near 10 MHz is first experimentally performed with indirect pumping from the ground state...
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The sub-Doppler absorption laser spectroscopy at 728nm transition from the 5D5/2 state to the 6F state of cesium with linewidth near 10 MHz is first experimentally performed with indirect pumping from the ground state 6S1/2 to the state 7P3/2 by a 455.5nm diode laser. Using a 455.5nm diode laser as an indirect pump laser, several excited states will be populated due to spontaneous decay from the 7P state. We first implement the sub-Doppler absorption laser spectroscopy at 728nm from the 5D5/2 state to the 6F state when Cs atoms within thermal glass cell decay to the 5D5/2 state. Due to velocity transfer effect, the hyperfine structure of 5D5/2 shows a mixed and complicated pattern but very e/ear structure when the 455.5nm pumping laser is counter-propagating （or co-propagating） with the 728nm probing laser.
We propose a kind of Yb2?–Yb3?-codoped glass,which is used as spectral converter layer to adjust AM1.5 solar spectrum for a better match with silicon *** energy-level rate equations and power transmission equations a...
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We propose a kind of Yb2?–Yb3?-codoped glass,which is used as spectral converter layer to adjust AM1.5 solar spectrum for a better match with silicon *** energy-level rate equations and power transmission equations are established to analyze the down-conversional effect of the codoped glass on solar *** numerical results show that with proper doping concentration and thickness the glass layer may improve conversion efficiency by about 12%.Moreover,we also apply the modified spectrum as excitation source of solar cell in a simulation platform,and reveal that there is about 15%improvement in practical cells.
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