  The authors report on a room-temperature nanoimprinted, DNA-based distributed
feedback (DFB) laser operating at 605 nm. The laser is made of a pure DNA host
matrix doped with gain dyes. At high excitation densities, the emission of the
untextured dye-doped DNA films is characterized by a broad emission peak with
an overall linewidth of 12 nm and superimposed narrow peaks, characteristic of
random lasing. Moreover, direct patterning of the DNA films is demonstrated
with a resolution down to 100 nm, enabling the realization of both
surface-emitting and edge-emitting DFB lasers with a typical linewidth<0.3 nm.
The resulting emission is polarized, with a ratio between the TE- and
TM-polarized intensities exceeding 30. In addition, the nanopatterned devices
dissolve in water within less than two minutes. These results demonstrate the
possibility of realizing various physically transient nanophotonics and laser
architectures, including random lasing and nanoimprinted devices, based on
natural biopolymers.
