Lambda-type doubling

Figure 4. Level scheme of a lambda-type double-resonance eperiment. The pump laser pulse couples the initial level 1 to a single rovibronic intermediate level 2 in the electronically excited Si state. The intermediate level 2 is coupled by the dump laser pulse to the vibra-tionally excited level 3 in the electronic ground state So- Ionization from level 2 is possible by absorption of an additional photon from the intense dump laser pulse. The coupling of the final level 3 to a single dark state (level 3a) is indicated and discussed in the text.

During cooling of hot solutions of /c- or t-type carrageenans, gelation occurs because the linear molecules are unable to form continuous double helices due to the presence of structural irregularities. The linear helical portions then associate to form a three-dimensional network in the presence of the appropriate cation. All salts of lambda-type carrageenans are soluble and non-gelling. 

FIGURE 5.10 Two-color lambda-type photoassociation spectroscopy of Rb2- Colliding, trapped ultracold Rb atoms are irradiated by lasers of frequencies vj and V2- Spontaneous emission from the excited level at frequency leads to loss of the atoms from the trap. Optical-optical double-resonance signals (free-bound-bound) are observed when the frequency difference V2 — vj coincides with the binding energy of a lower-state vibrational level. (From Tsai, C.C. et al., Phys. Rev. Lett, 79,1245, 1997. With permission.)... 

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