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1.
The stimulated radiation pressure acting on an atom nonadiabatically interacting with the field of counterpropagating frequency-modulated
waves is shown to reach high values typical for the rapid adiabatic passage of the instantaneous frequency of the field of
the counterpropagating waves through resonance with an atomic transition. Under the appropriate choice of interaction parameters,
the radiation pressure changes insignificantly in a wide range of atomic velocities.
Original Russian Text ? V.I. Romanenko, L.P. Yatsenko, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ
Fiziki, 2007, Vol. 86, No. 12, pp. 868–872. 相似文献
2.
The polarization and power spectra of radiation of two-level atoms moving in a field of biharmonic and monochromatic counterpropagating waves are computer simulated. It is shown that, as the frequencies of the counterpropagating waves are scanned with respect to the central frequency of the Doppler contour in the intensity distribution of groups of atoms moving at velocities that satisfy the resonance conditions for multiphoton transitions between quasi-energy levels, apart from well-known sub-Doppler resonances, narrow peaks appear. Such resonances should also occur for the stimulated light pressure force. 相似文献
3.
We present analytical results and numerical simulations for the force exerted on moving atoms in the fields of two counterpropagating waves whose amplitudes or phases are described as stochastic processes. We assume that one field repeats the other with some delay, as would occur when the two fields derive from a common source through a beam splitter and mirrors. We show that, just as with the force exerted by the field of two counterpropagating sequences of π-pulses, or two counterpropagating bichromatic or frequency-modulated waves, the force on an atom in counterpropagating stochastic waves may considerably exceed the force exerted by the field of a single running wave. For comparison we also discuss the interaction of an atom with two counterpropagating waves when one of them is monochromatic and the other one has a stochastic phase. In this case the force substantially exceeds the force exerted by the field of a single running wave but appreciably smaller then the radiative force in the counterpropagating waves in which one field repeats the other with some delay. 相似文献
4.
A. P. Bogatov 《Journal of Russian Laser Research》1994,15(5):417-453
The electromagnetic field inside a nonlinear active medium of a laser is considered as a system of counterpropagating waves.
Such an approach changes radically an earlier studied behavior of the lateral field instability due to self-deformaion (or
self-focusing). In our calculations we used an expression for a laser field in the form of two “strong” counterpropagating
waves whose complex amplitudes have weak perturbations. Amplitude perturbations of each of the “strong” waves can be presented
by two spatial harmonics corresponding to two weak perturbation waves with wave vectors making some tilted angle ±φ with the
cavity axis. Thus six waves would participate in the interaction: two counterpropagating strong waves and two pairs of weak
waves. Using this approach, we have developed a theory for the propagation of four “weak” perturbation waves in a nonlinear
amplifying medium in the presence of two counterpropagating “strong” waves. It is shown that perturbation waves with tilted
angle φ⋍0.5–1.2° inside the active region, and respecively, with the side lobes of the far-field pattern at ∼1.7–4°, have
the greatest growth increment. These perturbation waves produce lateral intensity modulation with period 10–30 μm for the
0.85 μm lasing wavelength. The appearance of such waves corresponds to the instability threshold of a homogeneous lateral
distribution of optical power in a diode laser.
The present theory makes it possible to investigate the stability of the homogeneous lateral optical intensity distribution
in a diode laser of any design. This allows one to choose a suitable design of a laser with a homogeneous lateral distribution
at high radiation power.
Translated from Preprint No. 43 (1992) of the Lebedev Physics Institute, Russian Academy of Sciences. 相似文献
5.
G. B. Malykin 《Optics and Spectroscopy》2001,91(5):795-800
Nonlinear Kerr effect leads to the appearance of a periodic structure in the saturated refractive index of an optical fiber, which corresponds to a standing structure formed by counterpropagating waves in the circuit of a fiber ring interferometer (FRI). If the intensities of counterpropagating waves are slightly different, their reflection from this periodic structure leads to the appearance of a phase shift of interference of counterpropagating waves unrelated to rotation at the FRI output. If a nonmonochromatic radiation source is used in the FRI system, only radiation rereflected from the middle of the circuit makes a contribution to the phase shift. A method for eliminating the influence of the nonlinear Kerr effect on the zero shift of fiber ring interferometers is proposed. This consists in making the middle of the circuit discontinuous. Numerical estimates are made. 相似文献
6.
F. Kh. Mirzade 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2008,2(4):669-676
Nonlinear dynamics of one-dimensional longitudinal waves in isotropic elastic plates was studied taking into account the interaction of displacement fields, temperature, and concentration of nonequilibrium (relaxing) atomic point defects. A nonlinear evolution equation for describing the self-consistent field of longitudinal thermoelastic strain was derived. The effect of generation-recombination processes on the evolution of nonlinear localized and periodic waves was analyzed. In the single-wave approximation, an equation was derived which describes the amplitude variation of nonlinear waves; based on this equation, characteristic features of damping of these waves were considered taking into account low-and high-frequency losses. The interaction of counterpropagating waves is briefly discussed taking into account dissipative effects. 相似文献
7.
E. G. Saprykin A. A. Chernenko A. M. Shalagin 《Journal of Experimental and Theoretical Physics》2014,119(2):196-205
The physical processes that form the resonances of saturated absorption and magnetic scanning in the field of counterpropagating waves of an arbitrary intensity when their polarizations change are numerically simulated. The atomic transition with level moment J = 1 is used as an example to show that the anomalies in the experimental saturated absorption spectra are determined by the degree of opening of the atomic transition. In the case of magnetic scanning, the anomalies are caused by the magnetic coherence induced by the wave fields at the levels of the lower state rather than by its transfer from the excited states, as was proposed earlier. 相似文献
8.
In the case of propagation of copropagating and counterpropagating surface waves along the interface of two media, the existence of a substantial difference in the spatial distribution of the energy flux components associated with the interference of active and reactive components of the field was established. The interference flux of the counterpropagating waves that is connected with the reactive components is undamped along the direction of propagation of the waves. 相似文献
9.
We have observed a novel type of parametric oscillation in sodium atomic vapor where four off-axis signal waves simultaneously build up under resonant and counterpropagating pump beams with elliptical beam profiles. The four waves, two of them Stokes shifted and the other two anti-Stokes shifted, have similar output powers of up to 10 mW with a conversion efficiency of 30% and are parametrically coupled by electromagnetically induced diffraction. 相似文献
10.
11.
Interference between inhomogeneous waves in a planar waveguide placed in a perfectly conducting environment is studied. It
is shown that the interference flux of copropagating waveguide TM modes behaves like counterpropagating homogeneous volume waves. The longitudinal and transverse components of the interference
fluxes of co-and counterpropagating waves in the general case result from interference between both the active and reactive
components of the field. The interference flux of waveguide modes may also be observed when the partial fluxes of the modes
equal zero. 相似文献
12.
The scattering of an atom in the field of counterpropagating light waves is studied under conditions such that the state of
the atom is a superposition of the ground and excited states. For the case in which this superposition is created by the field
of a traveling wave, the momentum distribution function of the atom after scattering by a standing wave is found analytically
in the approximation of a short interaction time, when the atom’s motion can be neglected. Longer interactions of the atom
with the field are studied numerically. We also consider the case of counterpropagating light waves consisting of Gaussian
or supergaussian pulses.
Zh. éksp. Teor. Fiz. 113, 563–572 (February 1998) 相似文献
13.
N. N. Rosanov 《JETP Letters》2012,95(12):609-612
It has been shown that counterpropagating electromagnetic waves with different frequencies generate two lattices in a cubically nonlinear medium, one of which moves at a superluminal velocity. When weak radiation reflects from the superluminal lattice, the wavefront is quasi-conjugated with distortions owing to the Doppler frequency shift. These effects occur both in insulators with fast nonlinearity and in an electron-positron vacuum. 相似文献
14.
The peculiarities of intra-Doppler structures that are observed in the atomic absorption spectrum of alkali metals with the help of two independent lasers have been studied. These structures accompany ultranarrow coherent resonances of electromagnetically induced transparency and absorption. With the D 2 line of rubidium taken as an example, it is shown that, in the scheme of unidirectional waves, the maximum number of satellite resonances caused by optical pumping selective with respect to the atomic velocity is equal to seven, while only six resonances are observed in the traditional scheme of saturated absorption with counterpropagating waves of the same frequency. The spectral position of the resonances and their polarity depend on the frequency of the saturating radiation, while their number and relative amplitude depend also on the experimental geometry. These features are of general character and should show themselves in the absorption spectrum on the D 2 lines of all alkali metals. An explanation of these features is given. The calculated spectral separations between the resonances are compared to the experimental ones, and their possible application is discussed. 相似文献
15.
Results of calculations of intensities, losses, and frequencies of counterpropagating waves in a ring resonator containing a weakly nonlinear active medium and an aperture are given. It is shown that inequalities of frequencies and intensities of generation of counterpropagating waves occur in such a resonator. The behavior of these inequalities is determined by the nonreciprocity of frequency-dependent losses of the counterpropagating waves. 相似文献
16.
D. V. Brazhnikov A. V. Taichenachev V. I. Yudin 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,63(3):315-325
We propose a new easy method to control a sign of the subnatural resonances of electromagnetically-induced transparency and
absorption in the Hanle configuration under counterpropagating light waves. The analytical results for a three-level atomic
Λ-scheme are corroborated by numerical calculations for various atomic transitions. The results can be applied in nonlinear
optics, optical communications and magnetometry. 相似文献
17.
N. N. Rozanov 《Optics and Spectroscopy》2008,104(2):248-252
The generation of counterpropagating waves with low frequencies by pump copropagating waves in a weakly nonlinear medium is analyzed. The generation is shown to be efficient in the presence of intervals with anomalous and normal dispersion in the spectrum. Under these conditions, the approximation of unidirectional propagation, which is widely used in the literature, is incorrect and the nonlinear propagation of radiation should be described by the full wave equation. 相似文献
18.
Kh. B. Tolipov 《Technical Physics》2014,59(3):460-462
An acoustic field near the edge of an elastic wedge-shaped plate is studied. The field is represented in the form of two counterpropagating nonuniform waves. The standing vibration profiles varying with distance to the edge are constructed. A specific acoustic effect arising when the wave moves away from the wedge is revealed. Theoretical results are confirmed by measuring the standing wave amplitudes with a proprietary setup. 相似文献
19.
T. V. Radina 《Optics and Spectroscopy》2000,88(1):132-138
An analysis is made of the problem of generating the fundamental mode in a laser cavity containing a weakly nonlinear active medium and an aperture. Frequency-dependent nonlinear loss of counterpropagating waves is calculated. The loss was found to have a jumpwise decrease at the boundary of the lasing region. An explanation is given regarding the mechanism responsible for the asymmetry of loss about the central frequency of the transition. It is shown that counterpropagating waves differ in loss, as well as in the phase velocity, which is one of the reasons of that the counterpropagating waves of a ring laser, without special nonreciprocal devices, have different frequencies and intensities. 相似文献
20.
D. V. Brazhnikov A. V. Taichenachev A. M. Tumaikin V. I. Yudin V. L. Velichansky S. A. Zibrov 《Journal of Experimental and Theoretical Physics》2009,109(1):11-22
The saturated absorption resonance in an atomic gas in the field of counterpropagating light waves with an arbitrary elliptical polarization is investigated. A conclusion about the peculiarities of the resonance shape is drawn from a general analysis of the symmetry of the problem. In particular, a new effect has been found: the polarization parameters of the light waves can lead to an asymmetry and shift of the resonance. These conclusions are corroborated by an approximate analytical solution for the F g = 1 → F e = 2 transition and by numerical calculations. Apart from their fundamental importance, the results obtained can have important applications in metrology (frequency and time standards). 相似文献