Optical double resonance measurements

Chen Y, Topp MR (2002) Infrared-optical double-resonance measurements of hydrogenbonding interactions in clusters involving aminophthalimides. Chem Phys 283(l-2) 249-268... 

Silvers S.J., Gottscho, R.A. and Field, R.W. (1981). Collisional depolarization of state selected (J,Mj) BaO A1S+ measured by optical-optical double resonance, J. Chem. Phys., 74, 6000-6008. 

Fig. 2. Excitation spectrum of the 1/S o —> 3 Po resonance of a single indium ion obtained in optical-optical double resonance using electron shelving. The linewidth of the fitted lorentzian is 170 Hz FWHM. The average excitation probability in the peak is about 10% and the total measuring time was 30 minutes...

Optical-optical double-resonance utilizing quantum amplification - was used to detect transitions of the ion driven by the 281.5 nm laser to the metastable 5/2 state. This method makes use of the fact that the 194 nm fluorescence intensity level is bistable high when the ion is cycling between the S and P states (the "on" state) and nearly zero when it is in the metastable D state (the "off" state). The fluorescence intensity in the on state is high enough that the state of the atom can be determined in a few milliseconds with nearly 100% efficiency. The full measurement cycle was as follows A series of measurements of the 194 nm fluorescence was made, using... 

TiN has an X 2S+ ground state and rotational transitions in the v = 0 level have been measured and analysed [69, 70] pure millimetre wave and microwave/optical double resonance methods were used, over a frequency range from 37 to 446 GHz. 14N hyperfrne structure was observed for the two lowest rotational transitions, and the spectrum analysed using the conventional effective Hamiltonian, again expressed in cartesian form ... 

Millimeter wave spectroscopy with a free space cell such as a Broida oven is more sensitive than lower frequency microwave spectroscopy. However, the higher J transitions monitored by millimeter wave spectroscopy often do not show the effects of hyperfine structure. In the case of CaOH and SrOH, the proton hyperfine structure was measured in beautiful pump-probe microwave optical double resonance experiments in the Steimle group [24,68], They adapted the classic atomic beam magnetic resonance experiments to work with a pulsed laser vaporization source and replaced the microwave fields in the A and C regions by optical fields (Fig. 15). These sensitive, high-precision measurements yielded a very small value for the proton Fermi contact parameter (bF), consistent with ionic bonding and a... 

FIGURE 2.9 Alternating microwave-optical double resonance on individual Yb+ ion Scheme of excitation and detection (top). Temporal schedule of measurements (middle). Schematic... 

R. Bombach, B. HemmerUng, W. Demtroder, Measurement of broadening rates, shifts and effective lifetimes of Li2 Rydbeig levels by optical double-resonance spectroscopy. Chem. Phys. 121, 439 (1988)... 

The ground state hyperfine structure splitting of Ba" and of was measured with microwave optical double resonance. The following description is restricted to Ba since the experiments are similar for both isotopes. Pulsed laser light tuned to one of the hyperfine components of the (6s 5i/2-6p Pi/2) resonance line at A = 493.4 nm produces a population difference between the F levels of the ground state by optical pumping. 

The same authors measured the nuclear magnetic dipole moment of Pr in an excited electronic state with rf-laser optical double resonance in CaF2 Pr. The precision was increased by two orders of magnitude in comparison to the best previous (atomic beam) measurement. The improvement was based on an appropriate choice of electronic state, crystal site symmetry, and magnetic field direction which minimized the electronic contribution to the nuclear moment to 3 x 10 . One of the six resolved... 

Spectroscopy utilizing tunable laser and microwave sources has been applied widely in exploring atoms, molecules, and condensed matter. Besides the classical areas of optical double resonance and optical pumping the extension of these or related methods to difference frequency measurements in the optical range seems to be of increasing importance. This includes heterodyne techniques. Laser microwave schemes can also play an essential role for the generation of modem frequen( standards. Last but not least, there will be many technical applications like infrared detectors, wavemeters, magnetometers, etc. 

Figare 54. Doppler-free spectrum of the 6s2ld and Rydberg states of Ba, obtained by optical-optical double resonance. All frequencies have been measured relative to Ba CD2). The hyperfine components of have been labeled F,-iy... 

Meth. MW MB IR MODR method of measurement used in the given reference corresponding to the preceding quoted values microwave spectroscopy molecular beam resonance experiment-electric or magnetic resonance infrared with lasers microwave optical double resonance... 

Meth. DR LA LM MB MW RA method of measurement applied to obtain the reported value double resonance experiments (microwave-optical double resonance MODR or radiofrequency-optical double resonance RFDR) Doppler free laser spectrosefipy laser magnetic resonance molecular beam electric resonance or molecular beam resonance with laser detection method microwave spectroscopy radio astronomy... 

A new very sensitive and accurate double-resonance technique is the Microwave-Optical double-resonance Polarization Spectroscopy (MOPS) developed by Ernst et. al [10.93]. This technique detects microwave transitions in a sample between crossed polarizers through the change in transmission of a polarized optical wave. The sensitivity of the method has been demonstrated by measurements of the hfs of rotational transitions in the electronic ground state of CaCl molecules which were produced by the reaction 2Ca+ CI2 - CaCl in an argon flow. In spite of the small concentrations of CaCl reaction products and the short absorption pathlength in the reaction zone a good signal-to-noise ratio could be achieved at linewidths of lf2 MHz [10.94]. 

We have shown in previous chapters that the -values of spectral lines are important fundamental data which must be known before detailed calculations of the behaviour of gas discharges, plasmas, or stellar atmospheres can be undertaken. Since it is difficult, in many cases, to make theoretical calculations of f-values to an accuracy of better than 20 per cent, experimental measurements of these quantities are essential. A considerable number of different techniques have been developed for this purpose, many of them involving the determination of radiative lifetimes. In this chapter we discuss two such techniques, namely the beam-foil and the delayed-coincidence methods. In Chapter 8 we shall discuss the determination of the f-values of resonance lines by studies of the profiles of spectral lines and in Chapters 15 and 16 the use of the Hanle effect and optical double resonance methods. 

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