lesson 12 time resolved spectroscopy Many phenomena are

lesson #12: time resolved spectroscopy Many phenomena are transient or pulsed in particular the de-excitation of molecules or atoms from an excited state Spectroscopy M. Casalboni 2019/’ 20 in molecules or impurities in solids ground state absorption emission 1/18

lesson #12: time resolved spectroscopy in molecules or impurities in solids Spectroscopy M. Casalboni 2019/’ 20 2/18

lesson #12: time resolved spectroscopy in molecules or impurities in solids Spectroscopy M. Casalboni 2019/’ 20 3/18

lesson #12: time resolved spectroscopy or more complex dynamic with different times (of the order of ps to s) Spectroscopy M. Casalboni 2019/’ 20 4/18

lesson #12: time resolved spectroscopy family of techniques based on time resolved measurements Spectroscopy M. Casalboni 2019/’ 20 we have already described electronic signal treatment (ATC, boxcar) in lesson # 10 now we focused on light sources pulsed lamps mandatory a short and intense pulse source lasers synchrotron radiation 5/18

lesson #12: time resolved spectroscopy Spectroscopy M. Casalboni 2019/’ 20 6/18

lesson #12: time resolved spectroscopy Spectroscopy M. Casalboni 2019/’ 20 dead time of the revelation chain 7/18

lesson #12: time resolved spectroscopy example Spectroscopy M. Casalboni 2019/’ 20 the measured intensity decay is convoluted with the lamp function 8/18

lesson #12: time resolved spectroscopy Spectroscopy M. Casalboni 2019/’ 20 9/18

lesson #12: time resolved spectroscopy light sources for fast time emission spectroscopy picosecond lasers Spectroscopy M. Casalboni 2019/’ 20 mode-lock: from 1980!! 10/18

lesson #12: time resolved spectroscopy femtosecond lasers Spectroscopy M. Casalboni 2019/’ 20 11/18

lesson #12: time resolved spectroscopy femtosecond lasers Spectroscopy M. Casalboni 2019/’ 20 Titanium: Sapphire laser down to 5 ps very stable easy operation 720 – 1000 nm need to be doubled or tripled and that pump day laser or OPO 12/18

lesson #12: time resolved spectroscopy parametric oscillator Spectroscopy M. Casalboni 2019/’ 20 13/18

lesson #12: time resolved spectroscopy faster device for transducing optical to elecrical signals PMT multi channel plate Spectroscopy M. Casalboni 2019/’ 20 long transit time (and spread) transit time very short 14/18

lesson #12: time resolved spectroscopy Spectroscopy M. Casalboni 2019/’ 20 15/18

lesson #12: time resolved spectroscopy Spectroscopy M. Casalboni 2019/’ 20 16/18

lesson #12: time resolved spectroscopy Spectroscopy M. Casalboni 2019/’ 20 17/18

lesson #12: time resolved spectroscopy Spectroscopy M. Casalboni 2019/’ 20 18/18