Time-delayed two-color two-photon ionization of anthracene, benzo [a] pyrene and pyrene in cyclohexane

Laser Two-Photon Ionization in Solution and on Surface in Ambient Air: Investigations Through Conductivity Measurement

“…This finding indicates that the intermediate excited state is the lowest excited state (Si) for the two molecules. 35 But the photocurrent behaves differently with the simulation based on the fluorescence lifetime and the laser pulse width for pyrene as shown in Fig. 9(b).…”

“…(a) Anthracene, (b) pyrene. Taken from(35). Reproduced with permission of the Elsevier Science B. V.increase, AQ, should be due to a combined effect of the two lasers .…”

Two‐Color Two‐Photon Ionization Spectrum of Pyrene in N‐Hexane

“…The apparatus used in this work is similar to that used in the previous work [11] except for the use of a dye laser for ionization. In brief, a small part of 337 nm light from an N2 laser (Molectron UV24, 3 mJ/pulse, 10…”

“…This large discrepancy in the two experiments has not been clearly explained, yet. In our previous work [11], we measured a photoconductivity of pyrene in n-hexane by means of the concerted irradiation of the second harmonics of an Nd-YAG laser and a nitrogen laser (total excitation energy: 5.65 and 6.01 eV), and found photoionization occurs at these energies. In the present work, we have measured the two-color ionization spectrum of pyrene using a nitrogen laser for the excitation of the intermediate state and a nitrogen-laserpumped dye laser for ionization:…”

“…Laser multiphoton ionization is useful in detecting a weak ionization signil because it has an advantage in sensitivity due to the use of a strong light source and tightly focused light enables the signal to increase even at low laser power [9][10][11]. Mechanism of the resonance enhanced multiphoton ionization (REMPI) can be probed by the two-color ionization method where one laser is used for the excitation to the intermediate state and the second laser for ionization [1,2,11]. Hoffman and Albrecht have measured weak ionization signal of N,N,N',N',-tetramethylphenylenediamine near the threshold by means of the two-color method [3].…”