首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   6篇
  免费   0篇
无线电   3篇
一般工业技术   3篇
  2020年   1篇
  2019年   1篇
  2018年   1篇
  2013年   2篇
  2003年   1篇
排序方式: 共有6条查询结果,搜索用时 15 毫秒
1
1.
We present results of a semianalytical and numerical study of transverse two-dimensional stationary and oscillating solitons in a wide-aperture laser with a saturable absorber and fast nonlinearity of both gain and absorption. We determine the stability conditions and bifurcations of axially symmetric solitons with screw wavefront dislocations of different order. We demonstrate the existence of asymmetric rotating laser solitons with different numbers of intensity maxima.  相似文献   
2.
Technical Physics Letters - Within the framework of linear acoustics, based on the linearized Navier–Stokes equations for a viscous liquid, the conservation rules for integral characteristics...  相似文献   
3.
Technical Physics Letters - An exact analytical expression has been derived for the area of an electric field generated by charged particles moving at constant acceleration in vacuum. An...  相似文献   
4.
Sols containing core/shell CdS/ZnS semiconductor quantum dots are synthesized and their nonlinear properties, which are interesting for a large variety of applications in nanophotonics, are studied. The quantum dots produced are smaller in dimensions than the exciton Bohr radius and, therefore, exhibit a well-pronounced quantum-confinement effect. The nonlinear optical properties of low-concentration sols are studied upon exposure to laser pulses with an emission wavelength of 532 nm and a duration of 5 ns by the z-scan technique. The dependences of nonlinear optical coefficients on the concentration of CdS/ZnS quantum dots are obtained. The intensity dependence of two-photon absorption coefficients is presented. The dependence determines the boundary of the influence of high-order nonlinearities on the nonlinear transmittance of the samples. The mechanisms of optical limitation exhibited by sols, specifically, two-photon absorption, nonlinear refraction, and nonlinear scattering are discussed.  相似文献   
5.
Abstract

A theoretical analysis based on coupled field-matter equations is given to describe the recently observed phenomenon of a central dark spot formation of a Gaussian beam transmitted through an absorbing defocusing liquid medium. We find that such a pattern formation, which is accompanied by normal defocusing rings in the far field, originates from interplay between the wave-front curvature of the Gaussian beam and strong spatial self-phase medulation arising from thermally induced refractive index change in the medium. Results of numerical analysis for a thin medium are shown to be in a good quantitative agreement with our experimental findings. Further, the dark spot formation is also predicted by using a focused Gaussian beam and self-focusing medium.  相似文献   
6.
The ferromagnetic resonance (FMR) spectra of thin metallic films obtained by magnetron deposition on polymeric and ceramic substrates are investigated in the strip line at frequencies of 0.13–12 GHz via frequency and external magnetic field sweeping. The influence of mechanical stresses on the FMR spectra of films deposited on an elastic (polyethylene rephthalate) substrate is discussed. The magnetostriction contribution to the anisotropy field of a film, as well as the influence of tensile stresses on the quasi-static permeability and FMR frequency, is estimated. It is demonstrated that the microwave properties of a thin metallic film are also specified by the properties of the substrate with such a film. A distinction in the magnetic properties of films with the same composition, which are deposited on different substrates, is explained in terms of the magnetostriction effect.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号