全文获取类型
收费全文 | 68篇 |
免费 | 0篇 |
专业分类
化学 | 6篇 |
晶体学 | 1篇 |
数学 | 1篇 |
物理学 | 60篇 |
出版年
2010年 | 1篇 |
2009年 | 4篇 |
2008年 | 1篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2002年 | 1篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 4篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有68条查询结果,搜索用时 281 毫秒
31.
We present a new “economic” method for performing two-photon spectroscopy using just one exciting dye-laser and taking advantage of the hereby produced broad emission bands of highly excited semiconductors. It is applied to the biexciton ground state in CdS (Ebiex = 5.0983 eV, symmetry Γ1) and to an excited biexciton state in ZnO (6.7407 eV, symmetry Γ5). 相似文献
32.
The 1Δg state of liquid oxygen (natural O2 and 18O2) was excited by intense Nd: YAG laser pulses. The observed fluorescence decay is non-exponential and depends on pump laser intensity. Various decay channels of the 1Δg state are discussed. The energy pooling reaction 1Δg + 1Δg → 1Σ+g + 3Σ?g is verified experimentally. Values f constant of liquid natural O2 and 18O2 are given. 相似文献
33.
Spatio-temporal structure formation and self-diffraction in CdS using laser-induced thermal gratings
M. L. Thoma C. Weber C. Klingshirn 《Applied Physics A: Materials Science & Processing》1991,52(4):255-260
The semiconductor CdS is well known to show various kinds of photo-thermal and photo-electric optical nonlinearities. We present here to our knowledge first results of spatiotemporal structure formation using laser-induced thermal gratings in CdS. By the means of an optical multi-channel analyzer the spatial resolution of transverse dynamic switching processes was observed directly. Spatially and time resolved self-diffracted signals were measured in the far-field. The experimental results agree very well with calculations obtained by solving the heat-flow equation and using a fast Fourier transformation. The calculations verify the experimental parameters, in particular the thermal diffusivity D0.1 cm2/s at room temperature. To obtain a better transverse structuring, CdS samples were also investigated which were fixed on a sapphire substrate for longitudinal heat sinking. 相似文献
34.
The diffraction from laser-induced gratings is observed in CdS at low temperature in the spectral region of the absorption edge. The excitation intensity is varied from about 100 W/cm2 to 1 MW/cm2. The reasons for the formation of gratings are a broadening of the excitonic absorption band, a new resonance due to two polariton transitions to the biexciton and the formation of an electron-hole plasma with increasing excitation intensities. 相似文献
35.
M. Lambsdorff C. Dörnfeld C. Klingshirn 《Zeitschrift für Physik B Condensed Matter》1986,64(4):409-416
We investigate thermally induced optical bistability (OB) in semiconductors using a cw-Argon-ion-laser beam pulsed by an electro-optic modulator. We obtain different types of OB due to absorptive and refractive changes with switching times in the order of ms. The different processes are modeled using a simple rate equation for the lattice temperature. Good agreement between theoretical predictions and the measurements are clearly to be seen. 相似文献
36.
37.
V. V. Zalamai V. V. Ursaki I. M. Tiginyanu A. Burlacu E. V. Rusu C. Klingshirn J. Fallert J. Sartor H. Kalt 《Applied physics. B, Lasers and optics》2010,99(1-2):215-222
High optical quality, well end leg faceted ZnO microtetrapods with leg length between 1 and 12 μm have been grown by carbothermal chemical vapor deposition. Lasing with mode quality factors of 2500–3000 is demonstrated. The origin of laser resonator cavity is discussed as a function of the tetrapod size. It is shown that in big tetrapods with legs of 12 μm in length the laser emission lines are well explained by longitudinal Fabry–Pérot modes generated in cavities formed by individual tetrapod legs. The dispersion of the ZnO refractive index is experimentally determined from the position of lasing modes in the temperature interval from 10 to 300 K. It is shown that the lasing mode structure is seriously affected by the decrease of the tetrapod size. For a small tetrapod with a leg length of 1 μm, the lasing modes cannot be explained anymore by the formation of longitudinal Fabry–Pérot modes in separate tetrapod legs, and the generation of guided modes by multiple total internal reflections in single tetrapod legs or in pairs of legs should be taken into account. The correlations between the lasing threshold and the tetrapod size are discussed. 相似文献
38.
A. Klochikhin A. Reznitskii L. Tenishev S. Permogorov S. Ivanov S. Sorokin Kh. Mumanis R. Seisyan C. Klingshirn 《JETP Letters》2000,71(6):242-245
Absorption and luminescence of the quantum wells formed by the (Zn-Cd)Se and (Ga-In)As solid solutions are studied in the range of exciton size-quantization ground state. The spectra observed are described by a model assuming the two-dimensional character of fluctuation states in quantum wells and the presence of a percolation threshold within the absorption contour. 相似文献
39.
Majumder F. A. Shevel S. Lyssenko V. G. Swoboda H. E. Klingshirn C. 《Zeitschrift für Physik B Condensed Matter》1987,66(4):409-418
The absorption-, reflection-, and luminescence spectra of CdS1–x
Se
x
are measured under low excitation. The luminescence under high excitation is also observed. For the first time, the gain spectra of disordered crystals are investigated with the excite- and probebeam technique to get a better understanding of the high density electron-hole pair system in this type of materials. We compare the results with those obtained in pure CdS and CdSe. 相似文献
40.
Excitons are the energetically lowest excitations of the electronic system in an ideal semiconductor at zero temperature. If the excitons couple to the electromagnetic field, a mixed state is formed, the quanta of which are called excitonic polaritons. Associates of two excitons, so-called biexcitons, have been observed in many semiconductors. Excitons are known for about forty years. During the first three decades, they have been investigated mainly by the classical spectroscopic methods, i.e., reflection, transmission and luminescence spectroscopy. In the last decade, several new techniques have been developed, which allow for a direct spectroscopy in momentum space. In this contribution, we review these novel techniques, both linear and nonlinear ones, and present results obtained for excitons, polaritons and biexcitons. The review is restricted to semiconductors which have their conduction band minimum and their valence band maximum at the same point of the Brillouin zone (direct-gap materials) and which have a band to band transition which is dipole allowed. 相似文献