Atomic coherence transfer

We performed an experiment to verify the atomic coherence transfer process with Rb. Fig. 22(b) shows a related level diagram of Rb. We choose the sublevels... 

STIRAP process, atomic coherence transfer between different spin levels is proposed theoretically and demonstrated experimentally. 

Two-dimensional homonuclear correlation spectroscopy (COSY) is well established for the study of liquids [24,25] and has recently been shown to be effective with solid samples [8,26-38], many of which are of catalytic interest [30,37]. The COSY spectrum contains diagona] peaks and off-diagonal cross-peaks. The cross-peaks arise because of coherence transfer between spins, and they indicate that the resonances at the relevant shift positions on the two axes are coupled. In the solid state, the necessary coherence transfer may occur through dipolar or scalar interactions. Experiments based on scalar couplings have been more popular, because in favorable circumstances they allow the spectroscopist to establish unambiguously the atomic connectivities within molecules in solid samples [8,27-38] including complex zeolitic frameworks [8,30-37]. 

A nearly identical polysfyrene sample was prepared, but with imiform labeling of all the polymer backbone carbons. This permitted the use of the pulse sequences shown in Figure 18. The nmning of these sequences follows the convention used by those working in the protein structure area. Listing the atoms in the coherence transfer pathway forms the acronym. Those atoms in the coherence transfer pathway whose chemical shifts are not encoded during... 

In the interaction of a coherent laser beam with an ensemble of particles (atoms or molecules), one may treat the individual particles as nearly stationary, because even for a fast atomic/molecular beam the particles move only a few micrometres on the time-scale of the photon interaction. Consequently, if the laser photons are absorbed in the interaction, the coherence properties of the laser radiation are transferred to the particle ensemble. It is this coherence transfer that is exploited in experiments such as the orientation of reagents in chemical reactions, or the probing of intramolecular motion in transition states and orientation of products. 

The STIRAP method has attracted considerable interest as a highly efficient way to coherently transfer atom pairs or Feshbach molecules into a more deeply bound state [85]. The method offers a high transfer efficiency without heating of the molecular... 

If the pulses dJi and CO2 have the same time back edge, the maximal atomic coherence between l) and 12) is reached. In step-2, we apply a STIRAP process among states 2, 3 and 14, the pulse sequences are shown in the right side of Fig. 23 (al). By simulation, we imd that the component of state 12 in the state vector is fully transferred to state 13 as shown in the right side of Fig. 23 (a2) and the coherence between l)- 2 is fully transferred to the coherence between l - 3 as shown in Fig. 23 (a3). Because the states 2 and 3 are not coupled with state 4 in the STIRAP process, it does not arouse the stimulated emission [53] from state 4 to l) when the pulse CO2 is applied. 

L. Wang, X. L. Song, A. J. Li and et al. Coherence transfer between atomic ground states by the technique of stimulated Raman adiabatic passage. Optics Letters 2008 Oct 15 33(20) 2380-2382. 

---