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1.
The optical pumping of Cs atoms with light of the D 1 line under magnetic resonance conditions is numerically calculated. This calculation is done to check the suggestion that an unexpectedly strong influence of the polarization of the pumping light on the resonance signals of transverse alignment, which we observed experimentally, is caused by the coupling between orientation and alignment by means of the magnetic field and/or the pumping light. This suggestion has been confirmed: upon circularly polarized pumping, the shape of the signal line of transverse alignment proved to be similar, as well as in the experiment, to the shape of the signal line of transverse orientation and was sharply different from the shape of the line of alignment observed upon linearly polarized pumping. For metastable 23 S 1 4He atoms, in accordance with the experimental data, the calculated shape of the signal line of transverse alignment is found to be independent of the polarization of the pumping light. The calculations also confirm the possibility of a reverse effect: the influence of alignment on orientation, which manifests itself in the occurrence of orientation upon pumping with unpolarized light under magnetic resonance conditions. For Cs atoms exposed to a field of ~0.6 Oe, the largest contribution to this effect is yielded by the field coupling of orientation and alignment, whereas, for metastable 23 S 1 4He atoms, the largest contribution is made by the light coupling of these polarization moments. 相似文献
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In an experiment with an optical pumping of 133Cs atoms in the 62 S 1/2 ground state, the line shape of the D 2f magnetic resonance signal for the transverse alignment component oscillating at a double frequency f of a radio-frequency (RF) magnetic field is found to strongly depend on the polarization of pumping radiation. On passage from a linearly polarized pumping light to a circularly polarized (CP) light with a sufficiently strong RF field the ordinary three-peak line with the highest central peak transforms into a two-peak line with a minimum at the center, so that the D 2f signal line resembles the M f signal line of a transverse orientation oscillating at the RF field frequency f. This suggests that the orientation (the first-rank polarization moment (PM)) arising upon CP pumping affects the alignment (the second-rank PM); i.e., the PMs of Cs atoms with different parities of their ranks become coupled. No influence of the polarization of a pumping radiation on the line shape of the D 2f signal is observed in a similar experiment with the 4He atoms in the 23 S 1 metastable state. 相似文献
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Optimization of parameters of the M x resonance, which excited between Zeeman sublevels of a single HFS level of the ground state of an alkali metal in a vacuum cell in a circuit with a single beam for pumping and detection (M x magnetometer circuit), has been carried out. A simple model taking into account all main factors controlling the resolving power of the M x resonance (including spin-exchange broadening and absorption in a thick layer of the cell has been constructed. It is shown that the spin-resonance broadening of the resonance line is mainly determined by the requirements imposed on the optical thickness of the cell, which considerably restricts the realization of advantages of ultranarrow (<1 Hz) lines in magnetometry. The experiment confirming the efficiency of the model has been carried out. 相似文献
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A change in polarization of a weak wave under optical pumping of atoms at an adjacent atomic transition is studied. It is shown that an elliptically polarized probe signal undergoes substantial polarization changes in the field of a circularly polarized pump wave. For the probe wave component with the same circular polarization as that of a strong signal, the medium becomes transparent. 相似文献
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<正>The relations between scattering angle(SA) and the degree of polarization(DOP) of skylights are studied. Measurements under different sky conditions demonstrate that all relation curves between SA and DOP can be described as parabolas.DOP reaches its peak when SA is 90°and the sizes of scattering particles are much smaller than the wavelengths of skylight.The peak value of DOP moves by a small drift when the size of the particle increases.We propose and analyze a polarization dependence model for SA and DOP.Results from simulation are in good agreement with experimental results. 相似文献
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L.C.M. Miranda 《Solid State Communications》1977,22(2):103-106
The effect of the simultaneous presence of an electromagnetic and a D.C. magnetic field on the magnon dispersion relation is discussed within the s-d-model. It is found that as the radiation frequency approaches the electron cyclotron frequency there is a quenching of the carrier contribution to the spin wave dispersion equation. 相似文献
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光磁共振实验测量gF值方法的改进与拓展 总被引:10,自引:1,他引:9
分析了光磁共振实验测量gF值中传统方法存在的问题,提出了利用光抽运信号的变化来判断合磁场方向的改进措施,避免了实验过程中对合磁场的方向和大小的误判以及光抽运信号与共振信号的混杂.同时,拓展了原有的测量方法,丰富了实验内容. 相似文献
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The spin-wave resonance spectrum of a ferromagnetic film magnetized normally to its surface is investigated as a function of the finite depth of penetration of the high-frequency field into the film with due regard for damping in the spin system and different types of surface-spin pinning. The exact numerical solution of the equation of motion for magnetization is obtained by considering the finite thickness of the skin layer. For a substantially inhomogeneous distribution of the high-frequency field over the layer thickness, the change in the resonance shape at frequencies close to the ferromagnetic resonance frequency is observed in addition to the broadening of all the resonance peaks and the decrease in their amplitudes. 相似文献
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The induction of higher polarization moments-the octupole orientation and the hexadecapole alignment—in the case of two-step excitation of atoms through dipole transitions and their manifestation in the polarization of dipole emission under conditions of anisotropic collisions are studied. For all channels of the two-step excitation process J 0→J 1 J, the efficiencies of production of higher polarization moments with integer and half-integer angular momenta from J=2 to J=7 through the absorption of linearly or circularly polarized light are calculated. The rates of collisional relaxation and interconversion of higher polarization moments, for both orientation and alignment, as functions of frequency detuning of the laser line from the center of the Doppler profile are calculated. The theory is illustrated by an example of two channels of excitation of the atomic state J=2 by circularly polarized light: J 0=0→J 1=1J=2 and J 0=3→J 1=2 (or 3)→J=2. In the first case, the octupole orientation enhances or attenuates the signal of circular polarization depending on the laser frequency detuning. In the second case, it represents the only source producing orientation and circular polarization of the emitted light. 相似文献
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The results of an investigation of the spectral and polarization dependences of the photostimulated diffusion of sodium in
heated gold are presented. It is shown that the light-induced increase in the diffusion rate is associated with optical excitation
of the electronic structure of the alloy NaAu, which forms in the subsurface layer of gold during the adsorption of the alkalimetal
atoms. The semiconductor properties of this alloy are revealed, and the gap width is estimated.
Zh. Tekh. Fiz. 68, 108–111 (October 1998) 相似文献
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Elliott H. Lieb Jan Philip Solovej Jakob Yngvason 《Communications in Mathematical Physics》1994,161(1):77-124
The ground state energy of an atom of nuclear chargeZe in a magnetic fieldB is exactly evaluated to leading order asZ in the following three regions:BZ
4/3,BZ
4/3 andZ
4/3BZ3. In each case this is accomplished by a modified Thomas-Fermi (TF) type theory. We also analyze these TF theories in detail, one of their consequences being the nonintuitive fact that atoms are spherical (to leading order) despite the leading order change in energy due to theB field. This paper complements and completes our earlier analysis [1], which was primarily devoted to the regionsBZ
3 andBZ3 in which a semiclassical TF analysis is numerically and conceptually wrong. There are two main mathematical results in this paper, needed for the proof of the exactitude of the TF theories. One is a generalization of the Lieb-Thirring inequality for sums of eigenvalues to include magnetic fields. The second is a semiclassical asymptotic formula for sums of eigenvalues that isuniform in the fieldB.Work partially supported by U.S. National Science Foundation grant PHY90-19433 A02Work partially supported by U.S. National Science Foundation grant DMS 92-03829Work partially supported by the Heraeus Stiftung and the Research Fund of the University of Iceland. 相似文献
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V. P. Danilov N. N. Il’ichev V. P. Kalinushkin M. I. Studenikin 《Bulletin of the Lebedev Physics Institute》2013,40(2):39-43
Experimental results and calculation data for the thermal conditions of the YAG:Er laser active element shaped as a flat plate under pumping by continuous radiation of a diode array (λ = 980 nm) with fiber output are presented. The thermal field and temperature in the plate optical excitation channel are measured using the thermal imaging technique. Their dependence on the pump power is studied. A comparison of calculated and experimental data allowed the determination of the heat transfer coefficient from the YAG:Er crystal to air under conditions of natural convection. 相似文献
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A. Ya. Silenko 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2012,6(1):176-181
General relations describing the spin dynamics of beams of nuclei with initial tensor and vector polarizations have been derived
upon planar channeling in bent crystals. The performed analysis indicates that the vector polarization effect predicted by
Baryshevsky and Sokolsky can be detected, occurring upon the planar channeling of a beam of nuclei with initial tensor polarization.
The planar channeling of a beam of nuclei with initial tensor and vector polarizations can be used to determine the quadrupole
moments of unstable nuclei with small lifetimes, up to 10−7 s. The quadrupole moments of nuclei with lifetimes of about 10−7 s cannot be measured via known methods, including optical methods. 相似文献