Time Evolution of the Excimer State of a Conjugated Polymer Laser

Wafa Musa Mujamammi; Saradh Prasad; Mohamad Saleh AlSalhi; Vadivel Masilamani

doi:10.3390/polym9120648

Time Evolution of the Excimer State of a Conjugated Polymer Laser

Polymers (Basel). 2017 Nov 27;9(12):648. doi: 10.3390/polym9120648.

Authors

Wafa Musa Mujamammi¹, Saradh Prasad^{2

3}, Mohamad Saleh AlSalhi^{4

5}, Vadivel Masilamani^{6

7}

Affiliations

¹ Department of Physics and Astronomy, College of Science, King Saud University, Riyadh 11451, Saudi Arabia. walmujammi@ksu.edu.sa.
² Department of Physics and Astronomy, College of Science, King Saud University, Riyadh 11451, Saudi Arabia. saradprasad@gmail.com.
³ Research Chair on Laser Diagnosis of Cancers, College of Science, King Saud University, Riyadh 11451, Saudi Arabia. saradprasad@gmail.com.
⁴ Department of Physics and Astronomy, College of Science, King Saud University, Riyadh 11451, Saudi Arabia. malsalhy@gmail.com.
⁵ Research Chair on Laser Diagnosis of Cancers, College of Science, King Saud University, Riyadh 11451, Saudi Arabia. malsalhy@gmail.com.
⁶ Department of Physics and Astronomy, College of Science, King Saud University, Riyadh 11451, Saudi Arabia. masila123@gmail.com.
⁷ Research Chair on Laser Diagnosis of Cancers, College of Science, King Saud University, Riyadh 11451, Saudi Arabia. masila123@gmail.com.

Abstract

An excited dimer is an important complex formed in nano- or pico-second time scales in many photophysics and photochemistry applications. The spectral and temporal profile of the excimer state of a laser from a new conjugated polymer, namely, poly (9,9-dioctylfluorenyl-2,7-diyl) (PFO), under several concentrations in benzene were investigated. These solutions were optically pumped by intense pulsed third-harmonic Nd:YAG laser (355-nm) to obtain the amplified spontaneous emission (ASE) spectra of a monomer and an excimer with bandwidths of 6 and 7 nm, respectively. The monomer and excimer ASEs were dependent on the PFO concentration, pump power, and temperature. Employing a sophisticated picosecond spectrometer, the time evolution of the excimer state of this polymer, which is over 400 ps, can be monitored.

Keywords: UV laser; amplified spontaneous emission spectra (ASE); conjugated polymer (PFO); time resolved study.