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Analysis on direct transforming the slow light into the stationary light pulse (SLP) is presented. Without the process of turning the slow light into the coherence between the lower levels, the generation of SLP is more efficient. The Maxwell-Liouville equations are employed to study the light pulse dynamics in the samples coherently driven by a bichromatic standing wave. The solution indicates that the forward and backward components of the SLP approach to each other exponentially. Such property is described by introducing a quantity called characteristic length, which appeared to be the ratio of the optical coherence decay rate and the coefficient of the driving term in Maxwell equation. The necessary length for completing the conversion can be estimated as five times the characteristic length. Several materials are analyzed here, including the 87Rb atoms with different densities, Pr3+-doped yttrium orthosilicate (Pr: YSO), and nitrogen-vacancy color centers in diamond (N-V centers). The values of the characteristic length for the corresponding materials are calculated, as well as the necessary length. [ABSTRACT FROM AUTHOR]

The Goos-Hänchen shift of the system composed by two cavity walls and an intracavity atomic sample is presented. The atomic sample is treated as a four-level double-A system, driven by the two counterpropagating coupling fields. The probe field experiences the discontinuous refractive index variation and is reflected. Moreover, under the phase-matching condition, the four-wave mixing effect based on electromagnetically induced transparency can cause effective reflection. The Goos-Hänchen shifts appear in both situations and are carefully investigated in this article. We refer to the first one with the incident and reflected light having identical wavelength as the linear Goos-Hänchen shift, and the second one with the reflection wavelength determined by the phase-matching condition as the nonlinear Goos-Hänchen shift. The differences between the two kinds of shifts, such as the incident angle range, conditions for the shift peaks, and controllability, are discussed. [ABSTRACT FROM AUTHOR]