A scheme for generating sub-Poisson light in a negative feedback and cascade three-level system is proposed in this paper. By using Langevin quantum theory, it is shown that there is a partial correlation between the ...A scheme for generating sub-Poisson light in a negative feedback and cascade three-level system is proposed in this paper. By using Langevin quantum theory, it is shown that there is a partial correlation between the two output light beams, one of which is fed back to control pump source so that the pump noise may be suppressed. When the pump noise is perfectly suppressed, the photon noise level of the internal field is 50% below the standard quantum limit (SQL), but the reduction of the output photon noise is related with the atomic number N. When N is very large, the output noise level is SQL. When N is very small, the sub-Poisson light can be produced within the cavity bandwidth in the external field, and the fluctuation of output photon flow approaches zero when N approaches 1. The conclusion in this paper is of generality.展开更多
A numerical design on the triangular photonic crystal fiber （PCF） based backward multi-pump Raman amplifier is presented. It is demonstrated that high flat Raman gain can be reached based on PCF. Influences of diffe...A numerical design on the triangular photonic crystal fiber （PCF） based backward multi-pump Raman amplifier is presented. It is demonstrated that high flat Raman gain can be reached based on PCF. Influences of different geometric parameters and germanium doping concentrations on the Raman net gain, amplified spontaneous emission （ASE） noise and double Rayleigh backscattering （DRBS） of the signal have been analyzed. For optimizing crystal fiber Raman amplifier （FRA）, there is tradeoff between the geometric parameter and germanium doping concentration of triangular PCF. The results show that PCF is an appropriate candidate for high gain Raman amplifiers.展开更多
基金the National Natural Science Foundation of China
文摘A scheme for generating sub-Poisson light in a negative feedback and cascade three-level system is proposed in this paper. By using Langevin quantum theory, it is shown that there is a partial correlation between the two output light beams, one of which is fed back to control pump source so that the pump noise may be suppressed. When the pump noise is perfectly suppressed, the photon noise level of the internal field is 50% below the standard quantum limit (SQL), but the reduction of the output photon noise is related with the atomic number N. When N is very large, the output noise level is SQL. When N is very small, the sub-Poisson light can be produced within the cavity bandwidth in the external field, and the fluctuation of output photon flow approaches zero when N approaches 1. The conclusion in this paper is of generality.
文摘A numerical design on the triangular photonic crystal fiber （PCF） based backward multi-pump Raman amplifier is presented. It is demonstrated that high flat Raman gain can be reached based on PCF. Influences of different geometric parameters and germanium doping concentrations on the Raman net gain, amplified spontaneous emission （ASE） noise and double Rayleigh backscattering （DRBS） of the signal have been analyzed. For optimizing crystal fiber Raman amplifier （FRA）, there is tradeoff between the geometric parameter and germanium doping concentration of triangular PCF. The results show that PCF is an appropriate candidate for high gain Raman amplifiers.
