A stable wavelength-tunable triggered source of single photons and cascaded photon pairs at the telecom C-band
K.D. Zeuner, M.  Paul, T. Lettner, C.R.R. Hedlund, L. Schweickert, S. Steinhauer, L. Yang, J. Zichi, M. Hammar, K.D. Jöns, V.  Zwiller, 112 (2018) 173102.