Bandwidth enhancement for parametric amplifiers operated in chirped multi-beam mode

In this paper we discuss the bandwidth enhancement that can be achieved in multi-Joule optical parametric chirped pulse amplification (OPCPA) systems exploiting the tunability of parametric amplification. In particular, we consider a pair of single pass amplifiers based on potassium dideuterium phosphate (DKDP), pumped by the second harmonic of Nd:glass and tuned to amplify adjacent regions of the signal spectrum. We demonstrate that a bandwidth enhancement up to 50% is possible in two configurations; in the first case, one of the two amplifiers is operated near its non-collinear broadband limit; to allow for effective recombination and recompression of the outgoing signals this configuration requires filtering and phase manipulation of the spectral tail of the amplified pulses. In the second case, effective recombination can be achieved simply by spectral filtering: in this configuration, the optimization of the parameters of the amplifiers (pulse, crystal orientation and crystal length) does not follow the recipes of non-collinear OPCPA.Comment: 11 pages, 5 figures. To appear in Opt.Com

Features of teaching the Russian history in educational organisations of the EMERCOM in modern realities

Проведен анализ Концепции преподавания курса «История России» для неисторических специальностей и направлений подготовки, выявлены перспективы ее реализации в образовательных организациях системы МЧС России. Особо отмечены своевременность и актуальность появления данного документа. Выделены факторы, обусловливающие в настоящее время повышенное внимание к вопросам изучения истории России, описан ряд обстоятельств, которые следует учитывать в процессе преподавания дисциплины. Рассмотрены особенности применения различных методических средств и приемов обучения в рамках курса «История России» в Уральском институте ГПС МЧС России (с учетом приоритетных задач будущей профессиональной деятельности обучающихся). Определена роль педагога как подлинного наставника-воспитателя, формирующего патриотическое историческое сознание студентов в процессе личностно-ориентированного преподавания исторической дисциплины.The purpose of the article is to analyse the Concept of teaching the course “History of Russia” for non-historical specialties and areas of training and identify prospects for its implementation in educational EMERCOM organizations. The timeliness and relevance of the document was emphasized. The factors that account for the increased attention to the issues of studying the history of Russia are highlighted, a number of circumstances that should be taken into account in the process of teaching the discipline is described. The features of the application of various methodical means and techniques within the course “History of Russia” in the Ural Institute of State Fire Service of EMERCOM of Russia (taking into account the priorities of future professional activity of students) are described. The role of the teacher as a genuine mentor-educator, forming the patriotic historical consciousness of students in the process of personal-oriented teaching of historical discipline, has been determined

Exawatt-Zettawatt Pulse Generation and Applications

A new amplification method, weaving the three basic compression techniques, Chirped Pulse Amplification (CPA), Optical Parametric Chirped Pulse Amplification (OPCPA) and Plasma Compression by Backward Raman Amplification (BRA) in plasma, is proposed. It is called C3 for Cascaded Conversion Compression. It has the capability to compress with good efficiency kilojoule to megajoule, nanosecond laser pulses into femtosecond pulses, to produce exawatt and beyond peak power. In the future, C3 could be used at large-scale facilities such as the National Ignition Facility (NIF) or the Laser Megajoule (LMJ) and open the way to zettawatt level pulses. The beam will be focused to a wavelength spot size with a f#1. The very small beam size, i.e. few centimeters, along with the low laser repetition rate laser system will make possible the use of inexpensive, precision, disposable optics. The resulting intensity will approach the Schwinger value, thus opening up new possibilities in fundamental physics.Comment: 13 pages, 4 figure

Numerical simulations for performance optimization of a few-cycle terawatt NOPCPA system

We present a systematic numerical design and performance study of an ultra-broadband noncollinear optical parametric chirped pulse amplification (NOPCPA) system. Using a split-step Fourier approach, we model a three-stage amplifier system which is designed for the generation of 7 fs pulses with multi-terawatt peak intensity. The numerical results are compared with recent experimental data. Several important aspects and design parameters specific to NOPCPA are identified, and the values of these parameters required to achieve optimal working conditions are investigated. We identify and analyze wavelength-dependent gain saturation effects, which are specific to NOPCPA and have a strong influence on the parametric amplification process. © Springer-Verlag 2007