全文获取类型
收费全文 | 61篇 |
免费 | 0篇 |
专业分类
化学 | 16篇 |
晶体学 | 1篇 |
数学 | 17篇 |
物理学 | 27篇 |
出版年
2022年 | 1篇 |
2019年 | 2篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 3篇 |
2012年 | 2篇 |
2011年 | 4篇 |
2010年 | 6篇 |
2009年 | 2篇 |
2008年 | 1篇 |
2007年 | 4篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2001年 | 4篇 |
1990年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有61条查询结果,搜索用时 296 毫秒
11.
V. V. Randoshkin N. V. Vasil’eva A. V. Vasil’ev V. G. Plotnichenko S. V. Lavrishchev A. M. Saletskii K. V. Stashun N. N. Sysoev A. N. Churkin 《Physics of the Solid State》2001,43(9):1659-1664
The optical absorption due to impurity ions was studied in gadolinium-gallium garnet single crystal films with a stoichiometric composition Gd3Ga5O12 grown by liquid-phase epitaxy from a supercooled PbO-B2O3 solution melt on (111)-oriented Gd3Ga5O12 substrates. 相似文献
12.
13.
S. I. Kablukov S. A. Babin D. V. Churkin A. V. Denisov D. S. Kharenko 《Laser Physics》2010,20(2):365-371
655 nm laser radiation with power of >60 mW is generated by frequency doubling of a broadband randomly-polarized 1.31-μm phosphosilicate
Raman fiber laser (RFL). The red power appears to grow linearly with increasing RFL power up to 7 W at efficiency comparable
with that for single-frequency lasers. It has been shown that multiple sum-frequency mixing processes involving different
RFL modes provide the main contribution to the output, which is enhanced by 2 times due to the modes stochasticity. 相似文献
14.
We construct a new explicit solution of the stochastic Schrödinger equation describing a quantum model of the interferometric detector of gravitational waves. For the evolution of this quantum model, we estimate autocorrelation functions of the detected signal and perturbations created by the measuring device. We discuss the influence of the characteristics of the measuring procedure on optimal choice of the length of the moving window which is used to estimate the frequency of gravitational waves by the method of correlation functions. 相似文献
15.
S. A. Babin D. V. Churkin A. E. Ismagulov S. I. Kablukov E. V. Podivilov 《Laser Physics》2007,17(11):1279-1285
Intracavity and output spectra broadened in a Raman fiber laser with a low-Q cavity are measured and theoretically described. It is demonstrated that the previously developed approach of optical-wave turbulence can be used to describe the spectral broadening owing to the multiple four-wave mixing processes that involves numerous longitudinal modes of the low-Q cavity. The theoretically calculated spectra are in good agreement with the experimental data for various output reflection coefficients of the fiber Bragg gratings across the entire power range. 相似文献
16.
A pulsed inductive nitrogen laser with a wavelength of 337.1 nm and a pulse power of 200 kW has been created. The excitation system of a cylindrical pulsed inductive discharge in nitrogen has been described. The spectral, energy, and temporal parameters of laser radiation have been investigated. Pulses with an energy of 2.4 mJ and a duration of 12 ± 1 ns have been generated. Laser radiation has the ring shape with an external diameter of 33 mm and a thickness of 1–1.5 mm. The divergence of radiation is 0.3 mrad. 相似文献
17.
A method for the condensation of nitroformylthiophenes with ketones of the aromatic and heterocyclic series by means of ammonium acetate in glacial acetic acid was developed. The method makes it possible to obtain thienyl-substituted , -unsaturated ketones with a nitro group in the heterocyclic ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1048–1049, August, 1980. 相似文献
18.
A. N. Ignatenkov A. I. Ponomarev L. D. Sabirzyanova T. B. Charikova G. I. Kharus N. G. Shelushinina A. A. Ivanov O. A. Churkin 《Journal of Experimental and Theoretical Physics》2001,92(6):1084-1089
The temperature dependences ρab(T) of Nd2?x CexCuO4+δ single crystals with 0≤x≤0.20 are studied and analyzed on the basis of the concepts in the theory of disordered 2D systems. The results are compared with the data obtained for other copper-oxide HTSC. It is found that a transition to the superconducting state in the optimal doping region 0.14≤x≤0.18 occurs only in crystals with a fairly small degree of disorder (k Fl≥2, where l is the mean free path). This transition is compatible with the weak 2D-localization mode as long as the localization radius is longer than the characteristic size of a Cooper pair. The superconducting transition temperature in the optimal doping region increases monotonically with the parameter k Fl characterizing the degree of disorder in the crystal. The degradation of superconducting properties upon a further increase in the doping level (x>0.18) is apparently associated with a transition from 2D to 3D conductivity in the single crystal. 相似文献
19.
Sergei K. Turitsyn Sergey A. Babin Dmitry V. Churkin Ilya D. Vatnik Maxim Nikulin Evgenii V. Podivilov 《Physics Reports》2014
The concept of random lasers exploiting multiple scattering of photons in an amplifying disordered medium in order to generate coherent light without a traditional laser resonator has attracted a great deal of attention in recent years. This research area lies at the interface of the fundamental theory of disordered systems and laser science. The idea was originally proposed in the context of astrophysics in the 1960s by V.S. Letokhov, who studied scattering with “negative absorption” of the interstellar molecular clouds. Research on random lasers has since developed into a mature experimental and theoretical field. A simple design of such lasers would be promising for potential applications. However, in traditional random lasers the properties of the output radiation are typically characterized by complex features in the spatial, spectral and time domains, making them less attractive than standard laser systems in terms of practical applications. Recently, an interesting and novel type of one-dimensional random laser that operates in a conventional telecommunication fibre without any pre-designed resonator mirrors–random distributed feedback fibre laser–was demonstrated. The positive feedback required for laser generation in random fibre lasers is provided by the Rayleigh scattering from the inhomogeneities of the refractive index that are naturally present in silica glass. In the proposed laser concept, the randomly backscattered light is amplified through the Raman effect, providing distributed gain over distances up to 100 km. Although an effective reflection due to the Rayleigh scattering is extremely small (∼0.1%), the lasing threshold may be exceeded when a sufficiently large distributed Raman gain is provided. Such a random distributed feedback fibre laser has a number of interesting and attractive features. The fibre waveguide geometry provides transverse confinement, and effectively one-dimensional random distributed feedback leads to the generation of a stationary near-Gaussian beam with a narrow spectrum. A random distributed feedback fibre laser has efficiency and performance that are comparable to and even exceed those of similar conventional fibre lasers. The key features of the generated radiation of random distributed feedback fibre lasers include: a stationary narrow-band continuous modeless spectrum that is free of mode competition, nonlinear power broadening, and an output beam with a Gaussian profile in the fundamental transverse mode (generated both in single mode and multi-mode fibres). 相似文献
20.
El-Taher AE Harper P Babin SA Churkin DV Podivilov EV Ania-Castanon JD Turitsyn SK 《Optics letters》2011,36(2):130-132
We experimentally demonstrate a Raman fiber laser based on multiple point-action fiber Bragg grating reflectors and distributed feedback via Rayleigh scattering in an ~22-km-long optical fiber. Twenty-two lasing lines with spacing of ~100 GHz (close to International Telecommunication Union grid) in the C band are generated at the watt level. In contrast to the normal cavity with competition between laser lines, the random distributed feedback cavity exhibits highly stable multiwavelength generation with a power-equalized uniform distribution, which is almost independent on power. 相似文献