Pixelated Laser with Tailored Emission Spectrum Photopatterned by Digital Holographic Microscopy

Abstract

Organic thin-film distributed feedback lasers provide broad spectral tunability and structural flexibility. However, the realization of spatially programmable multiwavelength emission across a 2D device area remains a challenge. In this study, this challenge is addressed through programmable fabrication of microresonator geometries using a system that integrates digital holographic microscopy with holographic lithography. Microresonators are first inscribed on an azobenzene-containing thin film as surface-relief gratings over localized regions known as pixels via holographic lithography. The pixelated pattern is then transferred onto the active medium using a soft-lithographic direct-transfer method to form the lasing structure. This approach enables controlled variation of the microresonator geometry, allowing precise tailoring of the laser emission spectrum. We demonstrate both single-wavelength emission from individual pixels and simultaneous multiwavelength lasing from collectively excited pixel arrays. The presented strategy provides a scalable platform for programmable organic laser arrays with arbitrary 2D spectral layouts.