Piotr Cegielski successfully defended his PhD thesis with distinction on May 16, 2019. Congratulations!

Within his dissertation “Development of Integrated Perovskite Lasers for Dielectric Photonic Circuits”, Piotr Cegielski has demonstrated the first metal-halide perovskite micro lasers monolithically integrated into silicon nitride photonic circuits (PICs).

These optically pumped lasers exhibited the lowest threshold of 4.7 μJ/cm² at room temperature, which is a record among CMOS compatible devices.  The demonstrated lasers are proving the concept that solution processed perovskite semiconductors can be used to fabricate lasers on silicon substrates as a high-performance yet cost effective alternative to expensive hybrid integration using III-V laser gain media.  Furthermore, in spite of inherent chemical sensitivity of perovskites, the lasers have been fabricated by standard semiconductor manufacturing techniques, such as a new photolithography process, which had never been demonstrated before for any perovskite devices. These results are the groundwork for further development of electrically driven low-cost perovskite micro lasers suitable for integration into PICs and CMOS chips.

The PhD thesis was supervised by Prof. Renato Negra, Chair of High Frequency Electronics at RWTH Aachen University and co-supervised by Prof. Max Lemme, Chair of the Institute of Electronic Devices, RWTH Aachen University/AMO GmbH. After his talk and the defense, Piotr was honored in good tradition as AMO’s new PhD with his doctoral hat and all AMO colleagues celebrated him with a nice barbecue.

The results have been published in Nano Lett., 2018, 18 (11), pp 6915–6923

Optics Express Vol. 25, Issue 12, pp. 13199-13206 (2017)

Microelectronic Engineering Volume 197, 5 October 2018, Pages 83-86,