Tunable distributed feedback (DFB) lasing output based on reflection grating configuration instead of the traditional
transmission grating type was realized from rhodamine 6G (R6G)-doped ethanol and DCM-doped methanol. Pure gain
coupling and additional index coupling were obtained in R6G-doped ethanol and DCM-doped methanol, respectively.
The tuning which was independent on the refractive index of the lasing media went through all of the tuning data for the
two cases. Dual-peak lasing emissions indicative of the existence of the index grating from the DCM-doped methanol
were observed. The interval between the dual peaks increased as the increasing of the pump energy. The effect can be
used to estimate the resonant nonlinear refractive index of luminescent materials.
Organic materials possessing quadratic non linear optical (NLO) properties are now part of the optical material panel available for applications. Up to now, the patterning of their optical properties for device fabrication is commonly achieved by the lithographic techniques derived from the microelectronic domain. We propose here an alternative method that allows a direct patterning of the NLO properties. The objective is to manufacture quasi phase matched devices for optical frequency conversion in guided mode and in the regime of free propagation.
We present a study of Distributed Feedback (DFB) Laser emission in polymer thin films. This laser scheme permits efficient control of the stimulated emission in dye doped polymer materials. Optical feedback is provided by distributed Bragg gratings formed in the film by interference patterns from the pump beam. We report on particular features of the thin film DFB lasers. Devices are optically pumped using a Lloyd-mirror interferometer. For a given DFB grating period, the number of lasing modes depends on film thickness. Spectral content of the devices can be analyzed using planar waveguide theory. An excellent agreement between the theoretical transverse electric mode structure and the laser emission spectrum is found. We report for the first time on another scheme in which two DFB gratings are optically excited. There results a multicolor laser emission. This new scheme can interpreted in terms of a degenerate four wave mixing (DFWM) process in which the coherent interaction between pump waves in the luminescent material is monitored by laser emission.
We present a study of Distributed Feedback laser emission in various polymer materials. This laser scheme permits efficient control of the stimulated emission in dye doped polymer materials. Optical feedback is provided by distributed Bragg gratings formed in the film by interference patterns from the pump beam. We demonstrate broad tunability of laser emission in polymeric waveguides doped with stilbenoid, phenylene vinylene and oligomers of phenyl ethynylene used for OLEDs. Laser action was also obtained with Rhodamine 6G in PMMA deposited on surface relief grating and excited in a transverse single beam pumping geometry.
We present a study of Distributed Feedback laser emission in various polymer materials. This permits efficient control of the stimulated emission in dye doped polymer materials. Confinement and waveguiding effects are evidenced. We also propose a dynamical study of the effect using 4 wave mixing in the saturable absorption regime with stimulated emission.