Biological Effect of Continuous, Quasi-Continuous and Pulsed Laser Radiation

In this work, for the first time, comparative studies of biological activity of low intensity continuous, quasi-continuous and pulsed laser radiation of nano- and picosecond time ranges with the same average power density are carried out. It is shown, that, despite the significant differences in peak values of intensity of acting factor, both continuous and quasi-continuous radiation and radiation of nano- and picosecond ranges are able to have both stimulating and inhibiting effects on all investigated parameters of functional activity of biological systems in a certain range of dose rates. The ability of laser radiation of near infra-red spectral region (800 - 1340 nm) located out the absorption bands of main chromophores of cells to have regulatory effect on biochemical processes that control the hatching of branchiopod crustaceans Artemia salina L. upon irradiation of their cysts is revealed. The role of molecular oxygen and water as acceptors of laser radiation is discussed. Keywords: Low intensity laser radiation, Laser activation, Biological activity, Zooplankton Artemia salina L., Sturgeon sperm

Генерация инфракрасного излучения при вынужденном комбинационном рассеянии

Equations describing the generation of medium-wave and long-wave infrared radiation in SRS are obtained in the situation when the frequency of the first or second Stokes components is smaller than the vibration frequency excited by the SRS process. It is shown that such generation occurs due to two-photon emission and four-photon parametric emission. In many cases, these equations make it possible to relatively simple estimate the efficiency of such generation of IR radiation.Получены уравнения, описывающие генерацию средневолнового и длинноволнового инфракрасного (ИК) излучения при вынужденном комбинационном рассеянии (ВКР) в ситуации, когда частота первой или второй стоксовых компонент меньше частоты колебания, возбуждаемого процессом ВКР. Показано, что такая генерация происходит вследствие двухфотонного испускания и четырехфотонного параметрического испускания. Во многих случаях полученные уравнения позволяют сравнительно просто оценить эффективность такой генерации ИК-излучения

Raman Threshold Lowering in Globular Photonic Structures Filled with Liquids

Stimulated Raman Scattering (SRS) in globular photonic crystals and glasses (at di˙erent diameters of the globules from 250 nm up to 2.3 mm) with embedded molecular liquids is studied under excitation with nanosecond or picosecond laser pulses. Substantial decrease of SRS threshold has been observed. Such a phenomenon is explained as the result of laser radiation field increase in globular photonic structures due to photonic density of states enhancement near the edges of photonic stop bands of photonic crystals, and due to Mie resonances or whispering gallery modes. Raman threshold lowering in globular photonic crystals and glasses opens the way to creating the new e˚cient laser sources based on composite globular photonic structures

Raman Threshold Lowering in Globular Photonic Structures Filled with Liquids

Stimulated Raman Scattering (SRS) in globular photonic crystals and glasses (at di˙erent diameters of the globules from 250 nm up to 2.3 mm) with embedded molecular liquids is studied under excitation with nanosecond or picosecond laser pulses. Substantial decrease of SRS threshold has been observed. Such a phenomenon is explained as the result of laser radiation field increase in globular photonic structures due to photonic density of states enhancement near the edges of photonic stop bands of photonic crystals, and due to Mie resonances or whispering gallery modes. Raman threshold lowering in globular photonic crystals and glasses opens the way to creating the new e˚cient laser sources based on composite globular photonic structures