Low-threshold photopumped distributed feedback plastic laser made by replica molding

We describe low-threshold photopumped organic distributed feedback (DFB) lasers with a polymer grating fabricated by replica molding, which is a soft imprinting method. These simply fabricated lasers oscillate at a low threshold comparable to that of organic DFB lasers precisely constructed using photolithographic technology. The threshold of laser oscillation was 250 nJcm-2pulse-1, that is, a peak-power threshold of 500 Wcm-2pulse-1.