Highly Efficient Circularly Polarized Light Emission in the Green Region from Chiral Polyfluorene-Thiophene Thin Films

A chiral polyfluorene-thiophene derivative incorporating two different chiral side chains was synthesized via the Suzuki coupling reaction. Upon photoexcitation, thin films of the polymer exhibited efficient circularly polarized luminescence in the visible range, even without thermal annealing. The dissymmetry factor, g(lum), of films with thicknesses less than 100 nm reached 0.2 at 505 nm.