Distributed feedback laser with methylammonium lead bromide embedded in channel-type waveguides

Distributed feedback (DFB) lasing is achieved with CH3NH3PbBr3 perovskite embedded in channel-type waveguides. By using a focused ion beam, DFB gratings are engraved within the bottom surface of channel-type waveguides etched on a SiO2/Si wafer. The oriented CH3NH3PbBr3 crystallized inside the waveguide with the DFB gratings shows second-order DFB lasing mode in lateral and normal directions above a threshold excitation density of 47 μJ cm−2 which is one order of magnitude lower than that in the non-DFB laser. The splitting DFB peaks are well reproduced by finite-differential time-domain calculation. The peaks change to a power-broadened amplified spontaneous emission as the excitation fluence is increased far above the threshold.