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High index of refraction via quantum interference in a three-level system of Er^3+-doped yttrium aluminium garnet crystal
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A simple three-level system is proposed to produce high index of refraction with zero absorption in an Er^3+-doped yttrium aluminium garnet (YAG) crystal, which is achieved for a probe field between the excited state 4I13/2 and ground state 4I15/2 by adjusting a strong coherent driving field between the upper excited state 4I11/2 and 4I15/2. It is found that the changes of the frequency of the coherent driving field and the concentration of Er^3+ ions in the YAG crystal can maximize the index of refraction accompanied by vanishing absorption. This result could be useful for the dispersion compensation in fibre communication, laser particle acceleration, high precision magnetometry and so on. 相似文献
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Junxiang Zhang Yabin Dong Haihong Wang Jiangrui Gao 《量子光学学报》2006,12(B08):74-74
The quantum coherence effects of the transition Fe = 2←→Fg = 3 depending on the polarization of the coupling and probe beam are observed in a Cs vapor cell. The splitting of electromagnetically induced transparency (EIT) window is observed when the degeneracy of two-level system is broken using a magnetic field. It is also shown that the splitted transparency points of two of three windows are shifted with the intensity of magnetic field ( i. e. Zeeman splitting in the upper and lower levels ) increasing. On the contrary, when we fix the intensity of magnetic field, and increase the Rabi frequency of the coupling beam, the splitted transparency peaks become wider. A qualitative agreement between experiment and theory is found. 相似文献
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Using Schroedinger-Maxwell formalism, we propose and analyse a cw four-wave mixing (FWM) scheme for the generation of coherent light in a five-level double-∧ atomic system based on electromagnetically induced transparency. We derive the corresponding explicit analytical expressions for the generated FWM field. The influence of hyperfine sublevel on the amplitude of the generated FWM field is predicted in detail. We also give a brief discussion on the experimental realization of the proposed scheme. 相似文献
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Jing Cheng 《量子光学学报》2006,12(B08):71-72
The effect of finite control beam on the transverse spatial profile of the slow light propagation in an electromagnetically induced transparency medium is studied. From the second-order wave equation and linear response of an EIT medium to the signal field, we find it is possible to produce an effective waveguide for the signal field. The existence and properties of a set of localized, stationary transverse modes are demonstrated. Especially, by carefully manipulating the profile of the control beam, we can realize single-mode propagation for the signal field, which may be important for potential applications. 相似文献
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In the presence of an applied static and uniform magnetic field, a cylindrical Kadomtsev-Petviashivili equation is derived for a relativistic electromagnetic solitary wave propagating in collisionless plasma consisting electrons, positrons, and ions in the case of weak relativistic limit. This equation is solved in a stationary frame to obtain explicit expression for the velocity, amplitude and width of solitons. The amplitude of the solitary wave has a maximum value at a critical αc of the ratio of the ion equilibrium density to the electron one, and it increases as the applied magnetic field becomes larger. 相似文献