Fruit-Enhanced Resistance to Microbial Infection Induced by Selective Laser Excitation
Figure 5
Comparison between the TPA of tr and the SPA of phenylalanine. (a) Two photon absorption spectrum of the tr over the excitation energy range relevant to the present work. Adapted from [23]. The blue arrow at the top right marks the two-photon excitation yield under the nonresonant conditions, that is, when the relative two-photon cross-section is negligible. The red arrow pointing to the maximum of the spectrum refers to the so-called resonant conditions. (b) Single-photon absorption of the phenylalamine adapted from [35]. Notice how by comparing both -axis values, the energy employed in any of the two laser excitation conditions is good enough to excite electronically, by energy transfer, the phenylalamine. See text for comments.
