Pedro H. Pereira presented the paper “Long-wavelength IR photovoltaic heterodyne receivers using patch-antenna QCDs” by A.Bigioli, G. Armaroli, A. Vasanelli, D. Gacemi, Y. Todorov, D. Palaferri, L. Li, A. G. Davies, E. H. Linfield and C. Sirtori during the LabSem’s paperclub meeting on April 27, 2020.