Highly Stable Lasing from Solution‐Epitaxially Grown Formamidinium‐Lead‐Bromide Micro‐Resonators

• Published in: Advanced optical materials 2022-06, Vol.10 (11), p.n/a
• Main Authors: Afify, Hany A., Sytnyk, Mykhailo, Rehm, Viktor, Barabash, Anastasiia, Mashkov, Oleksandr, Osvet, Andres, Volobuev, Valentine V., Korczak, Jędrzej, Szczerbakow, Andrzej, Story, Tomasz, Götz, Klaus, Unruh, Tobias, Schüßlbauer, Christoph, Thiel, Dominik, Ullrich, Tobias, Guldi, Dirk M., Brabec, Christoph J., Heiss, Wolfgang
• Format: Article
• Language: English
• Subjects: Epitaxial growth; Excitation; halide perovskites; Lasing; Materials science; microresonators; Optics; Perovskites; Photoluminescence; Refractivity; Room temperature; solution epitaxy; Substrates
• ISSN: 2195-1071; 2195-1071
• DOI: 10.1002/adom.202200237

High‐quality epitaxial growth of oriented microcrystallites on a semiconductor substrate is demonstrated here for formamidinium lead bromide perovskite, by drop casting of precursor solutions in air. The microcrystallites exhibit green photoluminescence at room temperature, as well as lasing with low thresholds. Lasing is observed even though the substrate is fully opaque at the lasing wavelengths, and even though it has a higher refractive index as the perovskite active material. Moreover, the lasing is stable for more than 109 excitation pulses, which is more than what is previously achieved for devices kept in the air. Such highly stable lasing under pulsed excitation represents an important step towards continuous mode operation or even electrical excitation in future perovskite‐based devices. Formamidinium‐lead‐bromide perovskite microresonators are formed simply by drop casting of precursor solutions on single crystalline lead‐sulfide substrates. The solution epitaxially grown resonators exhibit lasing with a low threshold and outstanding stability from ring‐cavity‐like modes, which are formed in spite of an unfortunate refractive index change from the perovskite to the substrate.