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Hertzian resonances

A. Kastler (Paris) discovery and development of optical methods for studying hertzian resonances in atoms. [Pg.1302]

In the past, optical methods have proven to be a powerful tool in the study of resonances among closely spaced sub-levels. A first example is the radiofrequency-optical double resonance technique Here a Hertzian resonance is induced by means of a rf field the light field is used to create the nonequilibrium population of the sublevels ("optical pumping") that is required for rf excitation, and to detect the rf-induced changes in the optical properties of the san le. [Pg.175]

In this contribution we present two laser spectroscopic methods that use coherent resonance Raman scattering to detect rf-or laser -induced Hertzian coherence phenomena in the gas phase these novel coherent double resonance techniques for optical heterodyne detection of sublevel coherence clearly extend the above mentioned previous methods using incoherent light sources. In the case of Doppler broadened optical transitions new signal features appear as a result of velocity-selective optical excitation caused by the narrow-bandwidth laser. We especially analyze the potential and the limitations of the new detection schemes for the study of collision effects in double resonance spectroscopy. In particular, the effect of collisional velocity changes on the Hertzian resonances will be investigated. [Pg.176]

Kastler, A. (1966). Optical methods for studying Hertzian resonances. In Nobel Lecturers, Physics 1963-1970, pp. 186-204. Elsevier, Amsterdam (1972). [Pg.289]

In the first part of the paper we discuss the Raman heterodyne detection of rf-generated sublevel coherence in atomic Sm vapor in the presence of rare gas perturbers. In a second part we report on the observation of novel Ramsey-type resonances due to collisional velocity diffusion in Sm vapor here the experimental technique uses counterpropagating laser fields and relies on coherent Raman processes to optically excite and detect Hertzian coherence. [Pg.176]

Quantum mechanically the modulation of the fluorescent light is associated with the radio frequency coherence of the excited state density matrix. In a standard Brossel-Bitter double-resonance experiment Tt-polarized light excites the atoms initially to the m=0 state of the excited level. Fig. 16.13(b), and then interaction with the r.f. magnetic field transforms each atom into a coherent superposition of the m=0, l states. The relative phases of the probability amplitudes of these states are fixed by the phase of the r.f. field and are the same for every atom of the sample. Thus the r.f. field is able to generate substantial hertzian coherence in the excited state density matrix. The fluorescent light emitted in the direction of B is then a coherent... [Pg.572]

Modulation of light from incoherent sources. The light beats observed in resonance fluorescence experiments should be clearly distinguished from those observed by Forrester et aZ.(1955). In that experiment an exceedingly weak modulation was detected in the light emitted from a conventional mercury lamp. In this source the atoms are excited by random collisions and the ensemble density matrix possesses zero hertzian coherence. The beat frequencies observed were due to the mixing at the detector of the radiation frequencies emitted by different atoms and... [Pg.582]

In this chapter we shall be concerned mainly with the principles of the technique, the effect of relaxation processes, and magnetic resonance transitions between Zeeman sub-levels. We shall therefore initially describe the experiments in terms of the populations of the ground state sub-levels. The discussion of the effects of phase coherence (Hertzian coherence) and experiments involving transverse pumping is reserved until section 17.8. Moreover the application of optical pumping methods to the investigation of hyperfine intervals and the measurement of nuclear moments is postponed until Chapter 18, as are the applications of this technique in devices such as magnetometers, atomic clocks, and masers. [Pg.593]


See other pages where Hertzian resonances is mentioned: [Pg.169]    [Pg.175]    [Pg.175]    [Pg.175]    [Pg.169]    [Pg.175]    [Pg.175]    [Pg.175]    [Pg.274]    [Pg.184]    [Pg.11]    [Pg.524]    [Pg.576]    [Pg.581]   


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