Maximal spin coherence

F-STIRAP is usually used to create maximal spin coherence. During the building of spin coherence by F-STIRAP, the medium memorizes the pulse information. The pulse information exists as spin coherence in the medium. So F-STIRAP is used as a technique of light storage. This technique is a different mechanism from the eonventional EIT-based processes [23,24]. In this section, we present our experimental researeh on light storage and release based on F-STIRAP in atomic vapor and Pr YSO crystal. 

Differential relaxation of in-phase and anti-phase operators involving a spin C [10], which are due to additional Tj relaxation effects active only for the anti-phase components and which depend on the geometry of the spin system, can lead to systematic errors of the coupling constant derived from cross-peak multiplets observed in an E. COSY-type experiment [11]. Since these errors depend for a given differential relaxation rate Ap on the frequency difference of the coherences with C in the a or yS state, according to Eq. (1) a remedy to the problem is to maximize the relevant J such that the condition J 3> Ap/2n is fulfilled ... 

Figure 4- SE signal as a function of the phase difference between the incident and scattered beams. The upper part of the figure shows the principle difference, in the case of deuterons and protons, between the scattering from a nucleus with and without nuclear spin. The lower part shows the NSE signals obtained in both cases—the count rate is plotted against the current of the phase correction coil. Acob und vdincoh ore the echo amplitudes for coherent and incoherent scattering, No is the average count rate outside the echo, N+ and iV are the maximal and minimal count rates with the ir/2-flippers on, and Nap and iVdown are the count rates of spin-up (rr-flipper off) and spin-down (ir-flipper on) measurements made with the nl2-flippers off.

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