Biexcitons generation in a polymer by a femtosecond electric pump pulse

► We theoretically study the photogeneration of biexcitons in a polymer. ► Dependence for the yields of biexcitons and excitons on the photoexcitations is showed. ► There exists a critical photoexciting intensity for their photogeneration. ► We can obtain biexcitons more efficiently by a stronger photoexciting intensity. ► The result is helpful to understand some experiments about polymer luminescence.