Influence of Blending Ratio and Polymer Matrix on the Lasing Properties of Perylenediimide Dyes

Abstract

Perylenediimide (PDI) dyes dispersed in polymer films have demonstrated great success as active materials in thin film organic lasers (TFOLs). The type of matrix used to host the dye and the dye doping rate are both crucial parameters to optimize laser performance. This work reports the study of two soluble PDIs, the comercial derivative perylene orange (PDI-O) emitting at around 580 nm , and a new dye (b-PDI-A) with subsituents at the 1,7 bay positions of the PDI core emitting at around 620 nm , dispersed at different doping levels (up to 8 wt% and 50 wt%, for PDI-O and b-PDI-A, respectively) in two widely used polymers for optoelectronics polystyrene (PS) and poly(methyl methacrylate) (PMMA). The main goal is to determine which of these two polymers, and at which dye concentration, provides the best results for their use in TFOLs. The assessment of the active materials has been carried out through the analysis of their absorption, photoluminescence and amplified spontaneous emission (ASE) properties. Their capability to form high quality optical waveguides has also been studied by determining gain coefficients and waveguide losses. Results have shown that for both types of PDI derivatives PS is better than PMMA at any concentration, that means larger photoluminescence efficiency, lower ASE thresholds, longer ASE operational lifetimes, larger gain and lower propagation waveguide losses. In addition, the onset concentration at which dye aggregation becomes significant as to negatively affect the optical properties is lower in PMMA than in PS, thus the larger the blending ratio, the larger the superiority of PS with respect to PMMA.

Solution-processed nanographene distributed feedback lasers

“…2, are as low as 45 μJ cm −2 (12 kW cm −2 ) and 30 μJ cm −2 (7 kW cm −2 ), for FZ1 and FZ2, respectively. These values are lower than those recently reported for other nanographenes (60 μJ cm −2 ) 10 and comparable to the ones of highly efficient laser dyes dispersed in PS, such as perylenediimides (PDI) 36 or COPV n 35 . A higher ASE threshold is obtained for FZ3 (Table 1), mainly attributed to the proximity between the absorption and the ASE emission that results in a much larger reabsorption.…”

Deep‐Red Lasing and Amplified Spontaneous Emission from Nature Inspired Bay‐Annulated Indigo Derivatives

“…These photostability results are superior to some of the most highly performing organic laser dyes which show line narrowing in the red and deep‐red part of the spectrum, though the pump intensity used in previously reported work should be taken into account. For direct comparison, perylenediimide derivatives showed more than 40% reduction in intensity when pumped at intensity twice the ASE threshold (λ pump > 500 nm) while a recently reported Squaraine derivative showed extremely rapid photo degradation even at intensities below the threshold when pumped using a N 2 laser similar to the one used in this work.…”

“…This adversely leads to photodegradation of the laser dyes and also limits the choice of pump source for these OSSLs . An inert polymer matrix such as polystyrene (PS) or poly(methyl methacrylate) (PMMA) that enables dispersion of the dye at a low doping concentration is useful to overcome the issues of concentration quenching and photodegradation . However, this approach is not practical for charge injection and charge transport because PMMA is not a semiconductor, restricting its applications in optoelectronic devices.…”

Dual Amplified Spontaneous Emission and Lasing from Nanographene Films

“…A film thickness (h f ) of around 600 nm was determined through the interference pattern observed in the non-absorbing region of the absorption spectrum [38]. Such films constitute planar waveguides that support just one transversal electric mode (TE 0 ) and one transversal magnetic mode (TM 0 ), both propagating with a high confinement factor (Γ approximately 90%) [39]. This minimizes waveguide losses and therefore the ASE threshold [40].…”