A scheme for generating the giant enhancement of the Kerr nonlinearity in a four-level system with the quantum coherences from the decays and the incoherent pumping is proposed. Compared with that generated in a gener...A scheme for generating the giant enhancement of the Kerr nonlinearity in a four-level system with the quantum coherences from the decays and the incoherent pumping is proposed. Compared with that generated in a general four- level system, the Kerr nonlinearity can be enhanced by several orders of magnitude with vanishing linear absorption. By using the numerical results, we show that the remarkable enhancement should be attributed to the interaction of the quantum coherences from the decays and the incoherent pumping.展开更多
The effects from quantum coherence via decays and incoherent pumping on the lasing without inversion(LWI) are investigated in a four-level system.By analyzing the transient and steady-state behaviors of the absorption...The effects from quantum coherence via decays and incoherent pumping on the lasing without inversion(LWI) are investigated in a four-level system.By analyzing the transient and steady-state behaviors of the absorption,we find that the gain occurs when both spontaneously generated coherence(SGC) and coherence induced by incoherent pumping(IPC) are considered.We attribute the occurrence of the gain to the interaction of quantum coherence via decays and incoherent pumping.展开更多
In this paper,we present a theoretical simulation of 87Rb absorption spectrum in a thermal cm-cell which is adaptive to the experimental observation.In experiment,the coupling and probe beams are configured to copropa...In this paper,we present a theoretical simulation of 87Rb absorption spectrum in a thermal cm-cell which is adaptive to the experimental observation.In experiment,the coupling and probe beams are configured to copropagate but perpendicular polarized,making up to five velocity selective optical pumping（VSOP） absorption dips able to be identified.A A-type electromagnetically induced transparency（EIT） is also observed for each group of velocity-selected atoms.The spectrum by only sweeping the probe beam can be decomposed into a combination of Doppier-broadened background and three VSOP dips for each group of velocity-selected atoms,accompanied by an EIT peak.This proposed theoretical model can be used to simulate the spectrum adaptive to the experimental observation by the non-linear least-square fit method.The fit for the high quality of experimental observation can determine valuable transition parameters such as decaying rates and coupling beam power accurately.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos.10904015,61008063,11004030,and 11074036)
文摘A scheme for generating the giant enhancement of the Kerr nonlinearity in a four-level system with the quantum coherences from the decays and the incoherent pumping is proposed. Compared with that generated in a general four- level system, the Kerr nonlinearity can be enhanced by several orders of magnitude with vanishing linear absorption. By using the numerical results, we show that the remarkable enhancement should be attributed to the interaction of the quantum coherences from the decays and the incoherent pumping.
基金Supported by National Natural Science Foundation of China under Grant Nos. 10904015,11074036,and 11004030
文摘The effects from quantum coherence via decays and incoherent pumping on the lasing without inversion(LWI) are investigated in a four-level system.By analyzing the transient and steady-state behaviors of the absorption,we find that the gain occurs when both spontaneously generated coherence(SGC) and coherence induced by incoherent pumping(IPC) are considered.We attribute the occurrence of the gain to the interaction of quantum coherence via decays and incoherent pumping.
基金Project supported by the National Basic Research Program of China(Grant No.2013CB922003)the National Natural Science Foundation of China(Grant Nos.91421305,91121005,and 11174329)
文摘In this paper,we present a theoretical simulation of 87Rb absorption spectrum in a thermal cm-cell which is adaptive to the experimental observation.In experiment,the coupling and probe beams are configured to copropagate but perpendicular polarized,making up to five velocity selective optical pumping（VSOP） absorption dips able to be identified.A A-type electromagnetically induced transparency（EIT） is also observed for each group of velocity-selected atoms.The spectrum by only sweeping the probe beam can be decomposed into a combination of Doppier-broadened background and three VSOP dips for each group of velocity-selected atoms,accompanied by an EIT peak.This proposed theoretical model can be used to simulate the spectrum adaptive to the experimental observation by the non-linear least-square fit method.The fit for the high quality of experimental observation can determine valuable transition parameters such as decaying rates and coupling beam power accurately.
