High‐Gain Broadband Solid‐State Optical Amplifier using a Semiconducting Copolymer

Abstract

A dilute fluorene copolymer produces enhanced optical amplification. High gain with 1000 times optical amplification and a long lifetime is achieve in only 1mm of the material, and exciton–exciton annihilation is suppressed.

Organic solid‐state integrated amplifiers and lasers

“…The corresponding gain obtained from a waveguide with a length of 122 μm at 530 nm was 12 dB, as shown in Fig. 26b [225]. Another favourable feature of this gain medium is the capability of providing high and even amplification of multiple pulses by virtue of its longer lifetimes and higher gains.…”

“…This is illustrated in Fig. 27, were amplification characteristics for a sequence of pulses along with probe beam coupling configuration used are displayed [225]. A high value for optical gain, 350 dB·cm 1 with a signal wavelength of 425 nm was obtained from a DFB amplifier based on a first-generation bisfluorene-cored dendrimer [226].…”

“…They are therefore, interesting for use in conjunction with polymer optical fibers for short haul communication applications. Amplifier sources reported in the literature are based on the copolymers MEH-PPV, F8BT, poly ((9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-(2,1 0 ,3)-thiadiazole)), (ADS233YE) [53,[223][224][225] as well as on bisfluorene-cored dendrimers [226]. Both F8BT and ADS233YE consist of fluorine (F8) and benzothiadiazole (BT) units however, the constituent parts in ADS233YE are in a higher statistical ratio.…”

“…Amongst the conjugated polymer amplifiers that have been developed, those based on the gain medium ADS233YE exhibited the highest gains, reaching 32 dB in a 1-mm-long structure at a wavelength of 560 nm [225]. The high gain values attained are attributed to the chemical structure of this specific gain material, which ensures larger chromophore separation, and hence alleviation of the adverse effect of exciton-exciton annihilation on the amplification process.…”

Electrically Tunable Organic Distributed Feedback Lasers Embedding Nonlinear Optical Molecules

“…Using organic semiconductors in laser devices represents the most fascinating and debated fi eld. [1][2][3] The interest towards organic lasers relies on their potential application to optical communications, [ 3 ] optical amplifi cation, [ 4 ] chemical sensing, [ 5 ] and gain switching. [ 6 ] However, the use of organic active media in laser devices is still delayed by the need of external sources for optical pumping and by the short operational lifetime.…”