During the work-packages carried out during this project, monolithic cavities on TMD monolayers in strong coupling regime have been successfully fabricated exploiting two different methods; the polarization behaviour of TMD monolayer cavities have been explored in photoluminescence (PL); valley depolarization dynamics have been analysed in the monolayers out of the cavity by means of circular dichroism pump probe experiments, observing valley selective Stark shift and inverse valley polarization between A and B excitons. Moirè heterostructures of MoSe2/WS2 with a small twist angle and TMDs homobilayers, all encapsulated in hBN, have been fabricated and fully characterized using static spectroscopy measurements; a hyperspectral microscope was optimized to perform widefield PL imaging of such structures; the ultrafast exciton behaviour for interlayer hybridized excitons has been explored by means of an ultrafast spectro-microscopy pump probe setup, finding different population times for the interlayer excitons. Strong coupling have been successfully reached in microcavities embedding both hBN-encapsulated moirè HSs of MoSe2/WS2 and MoS2 homobilayers; angle-resonant polariton amplification has not been observed in such systems, but enhanced optical nonlinearity has been observed in microcavity strongly coupled to hybridized interlayer excitons due the new effect of tunnelling-enabled phase space filling. Regarding the knowledge transfer between the researcher and the host institution and viceversa, the fellow has considerably broadened his scientific background on the ultrafast optics and photonics, hyperspectral microscopy, ultrafast dynamics of TMDs monolayers and bilayers and non-linear optical properties of 2D materials in microcavities. The fellow has worked with state-of-the-art femtosecond optical setups, learning how to generate ultrashort pulses using optical parametric amplifiers and characterize them, work with ultrafast transient absorption and circular dichroism setups at room and cryogenic temperatures, use common-path birefringent interferometers for hyperspectral imaging. The fellow has been trained in management skills, team working, time management, leadership and presentation skills, taking active part in the scientific and financial management of the project.The fellow transferred his knowledge by supervising 2 bachelor students, 3 master students and currently 1 PhD student. He has been also giving periodic seminars during the group meetings to transfer his previous knowledge in the field of exciton-polaritons and to show the latest results of the research to the group. Concerning the exploitation and dissemination of the results, a total of 6 papers have been published in international peer-reviewed journals, 1 submitted and uploaded on a public repository and 3 other manuscripts in preparation. The fellow gave a total of 9 oral contributions in international conferences and a seminar on 2D materials for the general audience during an outreach event. The fellow gave a seminar on 2D materials for the general audience during an outreach event, spread some of the results of the project on the national media, opened a twitter account for the project and updated the group website with the project results.
