Carbon-bridged oligo(p-phenylenevinylene)s for photostable and broadly tunable, solution-processable thin film organic lasers

Abstract

Thin film organic lasers represent a new generation of inexpensive, mechanically flexible devices for spectroscopy, optical communications and sensing. For this purpose, it is desired to develop highly efficient, stable, wavelength-tunable and solution-processable organic laser materials. Here we report that carbon-bridged oligo(p-phenylenevinylene)s serve as optimal materials combining all these properties simultaneously at the level required for applications by demonstrating amplified spontaneous emission and distributed feedback laser devices. A series of six compounds, with the repeating unit from 1 to 6, doped into polystyrene films undergo amplified spontaneous emission from 385 to 585 nm with remarkably low threshold and high net gain coefficients, as well as high photostability. The fabricated lasers show narrow linewidth (<0.13 nm) single mode emission at very low thresholds (0.7 kW cm−2), long operational lifetimes (>105 pump pulses for oligomers with three to six repeating units) and wavelength tunability across the visible spectrum (408–591 nm).

Synthesis of Dibenzo[hi,st]ovalene and Its Amplified Spontaneous Emission in a Polystyrene Matrix

“…To exploit the gain properties of the material and possibly employ these features in solid-state devices,w ee mbedded DBO 1 into ap olystyrene (PS) matrix by simply mixing solutions of these two compounds in toluene,with the amount of DBO 1 corresponding to either 10, 5, 3, or 1wt%.S uch dilution approaches have been used to inhibit intermolecular charge-transfer processes,a nd thus enhance SE signals [19a,20] and ASE/laser action in luminescent conjugated polymers. [21] Notably,t his method works effectively also for graphene molecules,a sb lending allows one to extend the SE signal of DBO 1 for about 70 ps in the 1wt% 1/PS blend (Figure 3b; see Figure S6 a-h for the spectra and dynamics of all the 1/PS films). Moreover,the PS blending leads to the recovery of the emission of DBO 1 in the solid state,and photoluminescence…”

“…'Such'dilution' approach'has'been'used'to'inhibit'intermolecular'charge;transfer' processes,'and'thus'enhance'SE'signals [19a,'20] 'and'ASE/LASER' action' in' luminescent' conjugated' polymers [21] .' Notably,' this' method' works' effectively' also' for' graphene' molecules,' as' blending'allows'one'to'extend'the'SE'signal'of'DBO'1'for'about' ≈'70'ps'in'the'1'w%'1:PS'blend' (Fig.'3bx'see'Fig.…”

Two-dimensional distributed feedback lasers with thermally-nanoimprinted perylenediimide-containing films

“…This threshold is significantly lower than that of device I (around 200 kW/cm 2 ), firstly because device II has a thicker film, which implies a higher film absorption, PL efficiency and a better confinement of the waveguide mode; and secondly, because device II emits closer to the wavelength of maximum gain (i.e. that at which ASE occurs, λ ASE = 581 nm) [19,20]. The DFB photostability half-life for device II is 1.7 × 10 4 pump pulses (28.3 min) under excitation at two times above threshold.…”

Chinoide/Aromatische Umwandlungen in π‐konjugierten Oligomeren: Raman‐Schwingungsspektroskopie an der Grenze zum π‐Bindungsbruch

“…[35] Anhand der COPVs konnte direkt die Beziehung zwischen optimaler p-Konjugation und maximaler Fluoreszenzquantenausbeute demonstriert werden, was kürzlich in ihrer Verwendung als herausragende Lasermaterialien resultierte. [36] Vond en COPVs wurden auch Rçntgen-Festkçrperstrukturen erhalten, die das Vorhandensein eines aromatischen Charakters in den Benzolringen unterstreichen. [34] Die Raman-Spektren der aromatischen COPV-Oligomere mit n = 1-6 sind in Abbildung 8g ezeigt, und entsprechend der Raman-Verschiebung von COPV1 wurde dieses erste Gruppenmitglied der Serie im aromatischen Minimum der allgemeinen BLA-Energie-Kurve platziert (Abbildung 9).…”