Facile layer-by-layer fabrication of semiconductor microdisk laser particles

Semiconductor-based laser particles (LPs) with an exceptionally narrowband spectral emission have been used in biological systems for cell tagging purposes. The fabrication of these LPs typically requires highly specialized lithography and etching equipment and is typically done in a cleanroom environment, hindering the broad adoption of this exciting new technology. Here, using only easily accessible laboratory equipment, we demonstrate a simple layer-by-layer fabrication strategy that overcomes this obstacle. We start from an indium phosphide substrate with multiple epitaxial indium gallium arsenide phosphide layers that are sequentially processed to yield LPs of various compositions and spectral properties. The LPs isolated from each layer are characterized, exhibiting excellent optical properties with a lasing emission full width at half maximum as narrow as