Laser saturation spectroscopy

This Doppler width can be avoided by typical sub-Doppler laser spectroscopy techniques. Laser saturation spectroscopy with a resolution close to the natural line width was used for a test of Special Relativity at the ESR. For such sub-Doppler resolution one must also take into account the small additional broadening and shift arising from the angle 0 between laser beam and ion beam in the Doppler formula. At an interaction length of 10 meters and more, angles are easily controlled to be better than 1 mrad. This limits a possible shift, which enters by... 

T. W. Hansch, I. S. Shahin, and A. L. Schawlow, Optical Resolution of the Lamb Shift in Atomic Hydrogen by Laser Saturation Spectroscopy, Nature Physical Science 235, 63-65 (1972). 

T. W. Hansch, M. H. Nayfeh, S. A. Lee, S. M. Curry, and I. S. Shahin, Precision Measurement of the Rydberg Constant by Laser Saturation Spectroscopy of the Bahner a Line in Hydrogen and Deuterium, Physical Review Letters 32, 1336-1340 (1974). 

Picosecond absorption spectroscopy has been employed to follow the time-dependence of the optical absorption during the formation of e, while pulsed-laser saturation spectroscopy has been used to examine the... 

Our present experimental arrangement for kinetic laser saturation spectroscopy with a g-switched ruby laser has been described in detail previously where it has been shown that the amplitude and temporal profile of the probe laser pulses contain the picosecond time history of the /i-level... 

Fig. 12. Schematic for laser saturation spectroscopy (LSS), showing depletion and recovery in a two-level system. Oscilloscope traces show four transmitted laser pulses at (a) low and...

T. W. H nsch, M.H. Nayfeh, S.A. Lee, S.M. Curry, I.S. Shahin Precision measurement of the Rydberg constant by laser saturation spectroscopy of the Balmer-a line in hydrogen and deuterium. Phys. Rev. Lett. 32, 1336 (1974)... 

However, when the frequency is coincident with the center frequency of the Doppler profile, the weak probe wave interacts with molecules whose absorption has already been reduced by the strong counterrunning wave. Consequently, the absorption of the probe wave has a resonant minimum equal in width to the homogeneous width and centered exactly on the Doppler-broadened absorption line. This method has been demonstrated in experiments using a CO2 laser operating at 10/um and SFe molecules (Basov et al. 1969), and now it is universally accepted in laser saturation spectroscopy. 

M.S. Feld "Laser Saturated Spectroscopy in Coupled Doppler-Broadened Transitions", in Ref. 1.6, pp. 369-420... 

A non-matheraatical account of laser saturation spectroscopy is given in the article by... 

Oscillator strengths or absorption cross sections may be obtained by applying saturation spectroscopy techniques to multistep photoionization spectroscopy. A few transitions in uranium have been studied.One of the advantages of saturation spectroscopy is that it can be applied to any one of the steps in the schemes shown in Fig. 2. The disadvantages are that the experimental requirements are severe (laser-atomic beam interaction area,-frequency,-band width and-polarization) and interpertation of the data can be complex. A detailed discussion will not be given because little application has been made to the lanthanides and actinides. We will discuss in the Autoionization section the determination of photoionization cross sections by a saturation method. 

The dephasing time, T2, can be measured by the photon echo technique or determined from the homogeneous width of saturation spectroscopy, which is a Fourier transform of the former, as easily seen from Eq. (5.35). When a sample is irradiated with three consecutive laser pulses at times, 0, t2, and f3, an echo pulse is emitted at time, t2 + t. This is called stimulated photon echo. Several additional echo techniques have been proposed. 

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