Nonlinear optical properties of benzimidazobenzophenanthroline type ladder polymers

1990 ◽  
Vol 56 (8) ◽  
pp. 712-714 ◽  
Author(s):  
J. R. Lindle ◽  
F. J. Bartoli ◽  
C. A. Hoffman ◽  
O.‐K. Kim ◽  
Y. S. Lee ◽  
...  
1992 ◽  
Vol 277 ◽  
Author(s):  
Samson A. Jenekhe ◽  
Michael F. Roberts ◽  
Jeffrey S. Meth ◽  
Herman Vanherzeele

ABSTRACTHost-guest molecular composites of conjugated rigid-rod polymers in the matrix of flexible-chain polymers were prepared from blend solutions of the Lewis acid complexes of the component polymers. Molecular composites of poly(p-phenylene benzobisthiazole) (PBZT) with the polyamides Nylon 66 and PTMHT were prepared and their linear and nonlinear optical properties were investigated by optical absorption and third harmonic generation spectroscopy, respectively. Dispersion of PBZT in a polyamide matrix was found to result in reduced π-electron interactions as evidenced by the narrowing of the main absorption band. The χ(3) spectra of composites were measured in the wavelength range 0.8–2.4μm which spans the resonant and nonresonant regions. Nonresonant χ(3) at 1.9μtm was studied as a function of composite composition and linear and nonlinear dependences of χ(3) with mole fraction of PBZT were observed for nylon 66 and PTMHT composites respectively. Our findings that both χ(3) and χ(3)/α can be enhanced in molecular composites suggest that this is an important approach to optimize materials for nonlinear optics. Preliminary results of our studies of other new molecular composites of rigid-rod and ladder polymers are also discussed.


1990 ◽  
Vol 214 ◽  
Author(s):  
Samson A. Jenekhe ◽  
Michael Roberts ◽  
Ashwini K. Agrawal ◽  
Jeffrey S. Meth ◽  
Herman Vanherzeele

ABSTRACTThe third order nonlinear optical properties of thin films of polybenzimidazobenzophenanthroline ladder (BBL) and semi–ladder (BBB) polymers and their model compound cis–BBB were investigated by picosecond, third harmonic generation. The χ(3) (−3ω, ω ω, ω) spectrum of BBL, BBB, and cis-BBB was obtained in the wavelength range 1.0–2.4µm and shown to exhibit a three–photon peak at respectively 1.695, 1.695, and 1.50 µm. The magnitude of the three–photon enhanced χ(3) was 6.40×10−11, 3.15×10−11, and 0.77×10−11 esu, respectively, for BBL, BBB, and cis–BBB. The results show that the χ(3) of BBL and BBB is enhanced by a factor of 50 and 17, respectively, relative to the model compound cis–BBB at 1.05µm.


2014 ◽  
Vol 6 (2) ◽  
pp. 1178-1190
Author(s):  
A. JOHN PETER ◽  
Ada Vinolin

Simultaneous effects of magnetic field, pressure and temperature on the exciton binding energies are found in a 9.0 1.0 6.0 4.0 GaAs P / GaAs P quantum dot. Numerical calculations are carried out taking into consideration of spatial confinement effect. The cylindrical system is taken in the present problem with the strain effects. The electronic properties and the optical properties are found with the combined effects of magnetic field strength, hydrostatic pressure and temperature values. The exciton binding energies and the nonlinear optical properties are carried out taking into consideration of geometrical confinement and the external perturbations.Compact density approach is employed to obtain the nonlinear optical properties. The optical rectification coefficient is obtained with the photon energy in the presence of pressure, temperature and external magnetic field strength. Pressure and temperature dependence on nonlinear optical susceptibilities of generation of second and third order harmonics as a function of incident photon energy are brought out in the influence of magnetic field strength. The result shows that the electronic and nonlinear optical properties are significantly modified by the applications of external perturbations in a 9.0 1.0 6.0 4.0 GaAs P / GaAs P quantum dot.


1990 ◽  
Author(s):  
Tapio T. Rantala ◽  
Mark I. Stockman ◽  
Daniel A. Jelski ◽  
Thomas F. George

Sign in / Sign up

Export Citation Format

Share Document