Efficient Emission Outcoupling from Perovskite Lasers into Highly Directional and Long-Propagation-Length Bloch Surface Waves

Halide perovskite micro‐ and nanolasers have become a novel platform for efficient generation of coherent emission in the whole visible range. However, the laser emission outcoupling from the perovskite microcrystals faces a number of problems related to large divergence angle, light‐soaking by a substrate, and high losses in the case of coupling with nanowaveguides. Here the perovskite nano‐ and microlasers are proposed to be integrated with a photonic crystal supporting Bloch surface waves (BSWs), which are coupled directly from the perovskite lasers with the efficiency of over 16%. The BSWs exciting at 535‐nm wavelength show high in‐plane directivity, down to 9, and long‐propagation length, up to 50 m. Moreover, a pronounced beam steering effect for the generated laser emission is demonstrated by varying the pumping laser beam position, which provides an additional degree of freedom for in‐plane control of the lasing mode outcoupling.