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Electron spectral density of the half-filled Hubbard model in the atomic limit at finite temperature
We have calculated the spectral function and density of states of halffilled two-dimensional Hubbard model in the Hubbard-I
approximation assuming an antiferromagnetic long range order at low temperature and compared results to the QMC data. It occurs
that calculated functions are in a qualitative agreement with the QMC one. We have also shown that Neel ordered state dispersion
has the similar form to the spin density wave one. 相似文献
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We investigated the effect of the mode composition (longitudinal and transverse modes) of laser radiation on the basic parameters
of the stroke pattern formed on a treated surface placed inside a laser cavity. We found that the contrast of the stroke pattern
formed by a laser beam with a complex set of longitudinal modes depends, in the first place, on the width of the laser radiation
spectrum and the laser cavity length and is virtually independent of the angle of rotation of the beam. In the region of small
rotation angles the broadening of strokes caused by the effect of transverse modes becomes predominant.
B. I. Stepanov Institute of Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated
from Zhurnal Prikaladnoi Spektroskopii, Vol. 64, No. 1, pp. 50–54, January–February, 1997. 相似文献
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To whom correspondence should be addressd. 相似文献
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The influence of changes in the refractive indices of the active medium and the loss modulator on the amplitude-detuning characteristic
of a CO2 laser was theoretically investigated. It is shown that at a comparatively great magnitude of sweeping the “instantaneous”
lasing frequency, the magnitude of the laser response increases not only in negative detunings, but also over a wide range
of positive detunings. The use of the procedure of changing the magnitude and sign of detuning as well as the range of sweeping
and the frequency of modulation makes it possible to realize various periodic and chaotic regimes of lasing, i.e., to exercise
control over the time and energy parameters of pulses over a very wide range.
B. I. Stepanov Institute of Physics of the Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 3, pp. 318–324, May–June, 1997. 相似文献
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G. G. Shakhov 《Journal of Applied Spectroscopy》1995,62(3):431-434
S. I. Vavilov State Optical Institute, Russia, 199034, St. Peterburg, Birzhevaya Liniya, 12. Translated from Zhurnal Prikladnoi
Spektroskopii, Vol. 62, No. 3, pp. 38–42, May–June, 1995. 相似文献
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To whom correspondence should be addressd. 相似文献
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Institute of Molecular and Atomic Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 2, pp. 145–150, March–April, 1995. 相似文献