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[en] Here is a review of the current way we handle source photons in Implicit Monte Carlo (IMC). A source photon is created with a randomly sampled position xp in the zone, a direction (Omega)p, a frequency vp sampled from the appropriate distribution, and a time tp uniformly sampled from (tn, tn+1). The source photons each have an energy Ep. The sum of Ep over all of the photons equals the energy of the source for that time step. In the case of thermal emission in a zone with Volume V, they would have Σp=1N Ep = σ pacT4VΔt, where N is the number of thermal source photons for that time step, and σp is the Planck mean opacity. Census photons do not differ from source photons in any way, except that they all start the time step with tp = tn. Then they advance each photon until it reaches the end of the time step. When they are done with all of the photons, they update the matter temperature using the difference between the emitted and absorbed energy, and proceed to the next time step.
[en] The transmission of 500 ns pulses through GaAs-AlGaAs heterostructures has been studied as a function of light intensity and wavelength. The intrinsic exciton absorption can be modeled by the sum of a small unsaturable background and a dominant term which saturates as a Bloch resonance. Corrections for the Gaussian transverse spatial profile and finite optical thickness lead to 150 W/cm2 for the uniform-plane-wave saturation intensity for an optically thin GaAs exciton transition. The nearly Bloch-like saturation curve does not imply that the free exciton transition is a simple saturable two-level system, but does suggest that it saturates as a homogeneously broadened line
[en] In this paper, the authors show new results on the electromagnetically induced transparency in ruby. At the powerful laser excitation, the authors observed the room-temperature Bose-Einstein polaritonic condensation, the ruby optical over-transparency and the traces of hidden photonic states. The results are crucial to the paraphoton lasing. (paper)
[en] We report the experimental observation of an optically controllable shift of the central frequency of a laser pulse, using a scheme based on dynamical electromagnetically induced transparency. This is evidence of frequency shift controllable by a coherent process. Original theoretical results are in agreement with the experimental data.
[en] The effect of self-induced transparency is investigated for a three-level system with a V-scheme of the allowed transitions in the case where one of the transitions is resonant while another one is quasiresonant. The generalized system of the wave and material equations for the resonant transition, taking into account the presence of a quasiresonant transition, is derived. This system is integrable, and its soliton solutions are investigated. It is shown that quasiresonant transition has an influence on the profile of the optical soliton and leads to its phase modulation. The conditions under which the propagation of the soliton is followed by the full inversion of the populations of quantum levels of the resonant transition are established. (letter)
[en] QIKMIX is a quick-turnaround computer code developed to compute the radiative Rosseland mean opacity of specified mixtures at specified temperature and density points. The QIKLIB data base, which QIKMIX uses, has been derived from the OPLIB library. For most mixtures, QIKMIX can compute opacities over a temperature range of 50 to 25,000 eV in less than 1 min of CDC 7600 computer time. The purpose of this report is to discuss the QIKLIB data base and the operation of the QIKMIX code
[en] In order to study the influence of the transparency and crown density of road green belts on particle dispersion, the green belts along Tinjing highway in Tianjin, China, were selected to study in this study and the green space was divided into four types, which respectively were the high crown density-high transparency green space, the low crown density-low transparency green space, the high crown density-low transparency green space and the low crown density-high transparency green space. The particle pollution concentration in sidewalk and green space was researched in the four types of green space. It was concluded that: in the sidewalk, the high crown density-high transparency green space was the most adverse to the diffusion of automobile exhaust pollutants because those contents of pm2.5, pm10 and dust were all the highest; in the green space, the high crown density-high transparency green space and the low crown density-low transparency green space were the most adverse to the diffusion of automobile exhaust pollutants because those contents of pm2.5, pm10 and dust were all the highest. So among the four types of green space, the high crown density-high transparency green space was the most adverse to pollutant diffusion. (paper)
[en] In this work we report on the development of a new method for computing mi- and high-Z NLTE opacities. A study has been performed using this method to assess the EOS and opacity sensitivities to the radiation field for both single species Au and multi-species SnNb and U3Au plasma cocktails with an emphasis on moderately to highly ionized systems. Developed as a benchmark tool, this capability will be used to assess both current and future in-line NLTE opacity capabilities.
[en] A four-level inverted-Y configuration driven by two control fields is considered to demonstrate the phenomenon of electromagnetically induced transparency (EIT). It is shown that the double EIT can be realized in this system. Such double transparency spectra can be locally modulated by changing the detunings as well as the Rabi frequencies of the control fields. (paper)
[en] While a criminal investigation and international inspection are similar in the purpose of identifying any possible violator, there are also differences between them. Especially in the case of a criminal procedure, the defendants are presumed to be innocent until he or she is convicted, but states must make efforts to prove their nuclear transparency. Let's compare both of them to find out the reason why these different points have happened