Curved-shape topological photonic crystal edge-state nanolasers in the telecom C-band

Flexible integrated photonics holds great potential for a wide range of applications beyond the capabilities of conventional rigid platforms. A mechanically bending nanolaser with an ultra-small mode volume and low power consumption could serve as a key building block for ultra-compact flexible photonic chips. Here, we present a curved-shape topological photonic crystal semiconductor nanolaser in the telecom C-band with a low lasing threshold of 4.5 kW/cm². Multi-wavelength lasing operations are observed in the fabricated nanolasers by slightly tuning the optical pump positions at the topological interface, demonstrating that higher-order modes can be selectively excited for lasing emission. The demonstrated bending topological edge-state nanolasers provide a promising approach toward ultra-compact light sources for flexible photonic chips.